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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2016	Feb. 28, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Trading Symbol	ETRM
Entity Registrant Name	EnteroMedics Inc
Entity Central Index Key	0001371217
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		6,873,878
Entity Public Float			$ 3,672,097

Consolidated Balance Sheets - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 3,310,787	$ 7,927,240
Accounts receivable (net of allowance for bad debts of $20,000 at December 31, 2016)	143,692	57,928
Inventory	1,789,578	1,686,324
Prepaid expenses and other current assets	476,624	831,495
Total current assets	5,720,681	10,502,987
Property and equipment, net	200,720	326,296
Other assets	1,119,405	757,802
Total assets	7,040,806	11,587,085
Current liabilities:
Current portion of convertible notes payable		717,391
Accounts payable	1,311,706	172,050
Accrued expenses	2,751,415	3,595,415
Accrued interest payable		1,172
Total current liabilities	4,063,121	4,486,028
Convertible notes payable, less current portion (net of discounts of $149,340 at December 31, 2015)		549,791
Common stock warrant liability	39,119	2,877,817
Total liabilities	4,102,240	7,913,636
Commitments and contingencies (Note 16)
Stockholders' equity:
Common stock, $0.01 par value; 300,000,000 and 13,333,333 shares authorized; 2,736,621 and 102,415 shares issued and outstanding at December 31, 2016 and 2015 respectively	27,366	1,024
Additional paid-in capital	303,852,582	281,252,963
Accumulated deficit	(300,941,382)	(277,580,538)
Total stockholders' equity	2,938,566	3,673,449
Total liabilities and stockholders' equity	$ 7,040,806	$ 11,587,085

Consolidated Balance Sheets (Parenthetical) - USD ($)	12 Months Ended
Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Consolidated Balance Sheets
Net of allowance for bad debts	$ 20,000
Convertible notes payable, less current portion, discounts		$ 149,340
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	300,000,000	13,333,333
Common stock, shares issued	2,736,621	102,415
Common stock, shares outstanding	2,736,621	102,415

Consolidated Statements of Operations - USD ($)	12 Months Ended
Consolidated Statements of Operations - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements of Operations
Sales	$ 786,660	$ 292,000
Cost of goods sold	431,476	125,047
Gross profit	355,184	166,953
Operating expenses:
Selling, general and administrative	17,981,525	19,892,424	$ 14,561,656
Research and development	5,169,286	8,141,323	11,031,619
Total operating expenses	23,150,811	28,033,747	25,593,275
Operating loss	(22,795,627)	(27,866,794)	(25,593,275)
Other income (expense):
Interest income	5,837	1,819	3,331
Interest expense	(4,104,003)	(939,182)	(530,222)
Change in value of warrant liability	3,512,816	3,295,536
Other, net	20,133	9,874	(8,554)
Net loss	$ (23,360,844)	$ (25,498,747)	$ (26,128,720)
Net loss per share-basic and diluted	$ (37.53)	$ (298.97)	$ (404.25)
Shares used to compute basic and diluted net loss per share	622,431	85,290	64,635

Consolidated Statements of Stockholders' Equity - USD ($)	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Total
Beginning Balance at Dec. 31, 2013	$ 606	$ 240,631,842	$ (225,953,071)	$ 14,679,377
Beginning Balance (in shares) at Dec. 31, 2013	60,599
Net loss			(26,128,720)	(26,128,720)
Employee stock-based compensation expense		6,138,384		6,138,384
Nonemployee stock-based compensation expense		181,323		181,323
Stock issued	$ 44	9,551,722		9,551,766
Common stock shares issued (in shares)	4,468
Exercise of stock warrants	$ 13	2,242,252		$ 2,242,265
Exercise of stock warrants (in shares)	1,265			1,265
Ending Balance at Dec. 31, 2014	$ 663	258,745,523	(252,081,791)	$ 6,664,395
Ending Balance (in shares) at Dec. 31, 2014	66,332
Net loss			(25,498,747)	(25,498,747)
Employee stock-based compensation expense		6,974,489		6,974,489
Nonemployee stock-based compensation expense		(34,712)		(34,712)
Issuance of common stock in registered public offering	$ 305	9,065,843		9,066,148
Issuance of common stock in registered public offering (in shares)	30,476
Stock issued	$ 46	6,392,326		6,392,372
Common stock shares issued (in shares)	4,604
Issuance of common stock for payments made in shares on senior amortizing convertible notes(Shares)	1,003
Issuance of common stock for payments made in shares on convertible notes payable	$ 10	109,494		109,504
Ending Balance at Dec. 31, 2015	$ 1,024	281,252,963	(277,580,538)	$ 3,673,449
Ending Balance (in shares) at Dec. 31, 2015	102,415			102,415
Net loss			(23,360,844)	$ (23,360,844)
Employee stock-based compensation expense		2,327,402		2,327,402
Nonemployee stock-based compensation expense		3,535		3,535
Common stock financing costs		(28,000)		(28,000)
Exercise of stock warrants	$ 14	4,986		$ 5,000
Exercise of stock warrants (in shares)	1,428			1,428
Issuance of common stock for payments made in shares on senior amortizing convertible notes(Shares)	2,632,778
Issuance of common stock for payments made in shares on convertible notes payable	$ 26,328	20,291,696		$ 20,318,024
Ending Balance at Dec. 31, 2016	$ 27,366	$ 303,852,582	$ (300,941,382)	$ 2,938,566
Ending Balance (in shares) at Dec. 31, 2016	2,736,621			2,736,621

Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($)	1 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Issuance of common stock net of warrants to purchase number of shares of common stock, shares	301,905
Issuance of common stock net of warrants to purchase number of shares of common stock, value	$ 6,003,932
Issuance of common stock in public offering for cash per share			$ 525.00
Payments of stock issuance costs public offering			$ 929,920
Exercise of stock warrants (in shares)		1,428		1,265
Exercise of stock warrants, per share		$ 3.50
Minimum
Exercise of stock warrants, per share				$ 1,197.00
Maximum
Exercise of stock warrants, per share				$ 2,299.50
At-The-Market
Payments of stock issuance costs public offering			$ 259,560	$ 284,698
At-The-Market \| Minimum
Stock issued, per share			$ 1,162.00	$ 1,157.80
At-The-Market \| Maximum
Stock issued, per share			$ 1,589.00	$ 2,664.20

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
Consolidated Statements of Cash Flows - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net loss	$ (23,360,844)	$ (25,498,747)	$ (26,128,720)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	139,576	188,606	188,904
Provision for doubtful accounts	20,000
Loss on sale of equipment		885
Stock-based compensation	2,330,937	6,939,777	6,319,707
Amortization of commitment fees, debt issuance costs and original issue discount	1,836,340	825,735	123,068
Change in value of warrant liability	(3,512,816)	(3,295,536)
Change in operating assets and liabilities:
Accounts receivable	(105,625)	(55,116)	14,930
Inventory	(103,254)	(705,805)	147,422
Prepaid expenses and other current assets	354,732	(409,822)	125,071
Other assets	(600,634)	349,709	(74,372)
Accounts payable	1,139,656	(222,636)	267,356
Accrued expenses	(891,060)	(235,351)	(355,294)
Accrued interest payable	2,097,199	(487,739)	(11,735)
Net cash used in operating activities	(20,655,793)	(22,606,040)	(19,383,663)
Cash flows from investing activities:
Purchases of property and equipment	(14,000)	(38,915)	(88,680)
Net cash used in investing activities	(14,000)	(38,915)	(88,680)
Cash flows from financing activities:
Proceeds from warrants exercised	5,000		2,242,265
Proceeds from sale of common stock and warrants for purchase of common stock		22,651,932	9,836,464
Common stock financing costs	(28,000)	(1,721,794)	(284,698)
Proceeds from convertible notes payable	17,250,000	1,500,000
Repayments on convertible notes payable	(446,867)
Repayments on notes payable		(3,000,000)	(4,000,000)
Debt issuance costs	(726,793)	(477,110)
Net cash provided by financing activities	16,053,340	18,953,028	7,794,031
Net (decrease) increase in cash and cash equivalents	(4,616,453)	(3,691,927)	(11,678,312)
Cash and cash equivalents:
Beginning of period	7,927,240	11,619,167	23,297,479
End of period	3,310,787	7,927,240	11,619,167
Supplemental disclosure:
Cash paid for interest	155,407	601,185	$ 418,889
Noncash investing and financing activities:
Conversion of convertible notes and interest payable	$ 20,318,024	$ 109,504

Description of the Business; Risks and Uncertainties of the Business	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Description of the Business; Risks and Uncertainties of the Business	EnteroMedics Inc. Notes to Consolidated Financial Statements (1)Description of the Business; Risks and Uncertainties of the Business Description of Business EnteroMedics Inc. (the Company) develops and sells implantable systems to treat obesity, metabolic diseases and other gastrointestinal disorders. The Company was incorporated in the state of Minnesota on December 19, 2002, originally as two separate legal entities, Alpha Medical, Inc. and Beta Medical, Inc., both of which were owned 100% by a common stockholder. Effective October 1, 2003, the two entities were combined and the combined entity changed its name to EnteroMedics Inc. The Company reincorporated in Delaware on July 22, 2004. The Company has devoted substantially all of its resources to recruiting personnel, developing its product technology, obtaining patents to protect its intellectual property, commercialization activities and raising capital and has recently commenced commercial operations in the United States deriving revenues from its primary business activity in 2015. The Company is headquartered in St. Paul, Minnesota. EnteroMedics Europe Sárl (EnteroMedics Europe), a wholly owned subsidiary of the Company, was formed in January 2006. EnteroMedics Europe is a Swiss entity established as a means to conduct clinical trials in Switzerland. Upon establishment there were 20 shares of EnteroMedics Europe issued and outstanding with a par value of 1,000 Swiss Francs. EnteroMedics purchased 100% of the shares and then issued one share to a fiduciary agent. The one share is the property of EnteroMedics and is held by the fiduciary in a fiduciary capacity under terms of the Fiduciary Agreement. The functional currency of EnteroMedics Europe has been determined to be the U.S. Dollar. During 2016, the Company’s board of directors and stockholders approved two reverse stock splits (collectively, the Reverse Stock Splits). Neither reverse stock split changed the par value of the Company’s common stock or the number of preferred shares authorized by the Company’s certificate of incorporation. The first reverse stock split was a 1-for-15 reverse split (the First Reverse Stock Split) of the Company’s outstanding common stock that became effective after trading on January 6, 2016. The First Reverse Stock Split also decreased the number of shares of common stock authorized by the Company’s certificate of incorporation proportionately, and proportional adjustments were also made to the Company’s outstanding stock options and warrants and the number of shares authorized under the Company’s Amended and Restated 2003 Stock Incentive Plan . In connection with the First Reverse Stock Split, an amendment to the Company’s certificate of incorporation was also approved to increase the number of shares of the Company’s common stock authorized for issuance to 150 million shares, effective immediately after the First Reverse Stock Split on January 6, 2016. The second reverse stock split was a 1-for-70 reverse split (the Second Reverse Stock Split) of the Company’s outstanding common stock that became effective after trading on December 27, 2016 pursuant to the Company’s Sixth Amended and Restated Certificate of Incorporation. In connection with the Second Reverse Stock Split, proportional adjustments were also made to the Company’s outstanding stock options and warrants. Additionally, in connection with the Second Reverse Stock Split, a second amendment was approved to increase the number of shares of the Company’s common stock authorized for issuance to 300 million shares, effective after the Second Reverse Stock Split on December 27, 2016. All share and per-share amounts have been retroactively adjusted to reflect the Reverse Stock Splits for all periods presented. Risks and Uncertainties The Company is focused on the design and development of medical devices that use neuroblocking technology to treat obesity, metabolic diseases and other gastrointestinal disorders and currently has approvals to commercially launch the vBloc System in the United States, the European Economic Area and other countries that recognize the European CE Mark. The Company has devoted substantially all of its resources to recruiting personnel, developing its product technology, obtaining patents to protect its intellectual property and raising capital, and has recently commenced commercial operations in the United States deriving revenues from its primary business activity in 2015 and 2016. The Company’s products require approval from the U.S. Food and Drug Administration (FDA) or corresponding foreign regulatory agencies prior to commercial sales. The Company received FDA approval on January 14, 2015 for vBloc Therapy, delivered via the vBloc System, and has begun a controlled commercial launch at select surgical centers in the United States. The vBloc System has also received CE Mark and was previously listed on the Australian Register of Therapeutic Goods (ARTG). The medical device industry is characterized by frequent and extensive litigation and administrative proceedings over patent and other intellectual property rights. Whether a product infringes a patent involves complex legal and factual issues, the determination of which is often difficult to predict, and the outcome may be uncertain until the court has entered final judgment and all appeals are exhausted. The Company’s competitors may assert that its products or the use of the Company’s products are covered by U.S. or foreign patents held by them. The Company’s activities are subject to significant risks and uncertainties, including the ability to obtain additional financing, and there can be no assurance that the Company will be successful in obtaining additional financing on favorable terms, or at all. If adequate funds are not available, the Company may have to further reduce its cost structure until financing is obtained and/or delay development or commercialization of products or license to third parties the rights to commercialize products or technologies that the Company would otherwise seek to commercialize.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

(2)Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying consolidated financial statements in conformity with accounting principles generally accepted in the United States of America. The Company’s fiscal year ends on December 31.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany transactions and accounts have been eliminated in consolidation.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. Cash and cash equivalents are primarily deposited in demand and money market accounts. At times, such deposits may be in excess of insured limits. Investments in money market funds are not considered to be bank deposits and are not insured or guaranteed by the federal deposit insurance company or other government agency. These money market funds seek to preserve the value of the investment at $1.00 per share; however, it is possible to lose money investing in these funds. The Company has not experienced any losses on its deposits of cash and cash equivalents.

Fair Value of Financial Instruments

Carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable and accrued liabilities approximate fair value due to their short maturities. The Company’s common stock warrants are required to be reported at fair value and the Company elected to report its senior amortizing convertible notes at fair value. The fair values of common stock warrants and investments in debt and equity securities, if any, are disclosed in Note 4. The fair value of the Company’s senior amortizing convertible notes is disclosed in Notes 4 and 8.

Common Stock Warrant Liability

The common stock warrants that were issued in connection with the July 8, 2015 public offering (the Series A Warrants) and the common stock warrants issued in connection with the November 9, 2015, January 11, 2016 and May 2, 2016 senior amortizing convertible notes (the Note Warrants) are classified as a liability in the consolidated balance sheets, as the common stock warrants issued provide for certain anti-dilution protections in the event shares of common stock or securities convertible into shares of common stock are issued below the then-existing exercise price. The fair value of these common stock warrants is re-measured at each financial reporting period and immediately before exercise, with any changes in fair value being recognized as a component of other income (expense) in the consolidated statements of operations.

Cash and Cash Equivalents

The Company considers highly liquid investments generally with maturities of 90 days or less when purchased to be cash equivalents. Cash equivalents are stated at cost, which approximates market value. The Company’s cash equivalents are primarily in money market funds and certificates of deposit. The Company deposits its cash and cash equivalents in high-quality credit institutions.

Short-Term Investments

The Company considers all investments with maturities greater than three months and less than one year at the time of purchase as short-term investments and classifies them as either available for sale or held to maturity. The Company also considers certain investments with maturities greater than one year but which are also held for liquidity purposes and are available for sale as short-term investments.

Available-for-sale securities are carried at fair value based on quoted market prices, with the unrealized gains and losses included in other comprehensive income within stockholders’ equity in the consolidated balance sheets. Realized gains and losses and declines in value judged to be other than temporary on available-for-sale securities are included in interest and other income. Interest and dividends on securities classified as available for sale are included in interest income. The cost of securities sold is based on the specific identification method.

Short-term investments in debt securities which the Company has the positive intent and ability to hold to maturity are reported at cost, adjusted for premiums and discounts that are recognized in interest income, using the interest method, over the period to maturity. Unrealized losses on held-to-maturity securities reflecting a decline in value determined to be other than temporary are charged to income.

Inventory

The Company accounts for inventory at the lower of cost or market and records any long-term inventory as other assets in the consolidated balance sheets.

Property and Equipment, Net

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation of property and equipment is computed using the straight-line method over their estimated useful lives of five to seven years for furniture and equipment and three to five years for computer hardware and software. Leasehold improvements are amortized on a straight-line basis over the lesser of their useful life or the term of the lease. Upon retirement or sale, the cost and related accumulated depreciation or amortization are removed from the consolidated balance sheets and the resulting gain or loss is reflected in the consolidated statements of operations. Repairs and maintenance are expensed as incurred.

Impairment of Long-Lived Assets

The Company evaluates its long-lived assets for impairment by comparison of the carrying amounts to future net undiscounted cash flows expected to be generated by such assets when events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Should an impairment exist, the impairment loss would be measured based on the excess carrying value of the asset over the asset’s fair value or estimates of future discounted cash flows. The Company has not identified any such impairment losses to date.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carry-forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance for deferred income tax assets is recorded when it is more likely than not that some portion or all of the deferred income tax assets will not be realized. The Company has provided a full valuation allowance against the gross deferred tax assets as of December 31, 2016 and 2015 (see Note 12). The Company’s policy is to classify interest and penalties related to income taxes as income tax expense in the consolidated statements of operations.

Medical Device Excise Tax

On January 14, 2015, the Company received FDA approval for vBloc Therapy, delivered via the vBloc Rechargeable System, and starting in the second quarter of 2015 revenues were generated from sales in the United States. As a result, the Company is now required to pay a quarterly medical device tax under the Affordable Care Act, which imposes a 2.3% excise tax on the sale of certain medical devices by device manufactures, producers or importers (the Medical Device Tax). The Medical Device Tax was effective on sales of devices made after December 31, 2012. The Company records the Medical Device Tax as an operating expense in the consolidated statements of operations, which totaled $1,363 for 2015. A moratorium was placed on the Medical Device Tax for 2016 and 2017 and, consequently, the Company was not required to pay the Medical Device Tax in 2016.

Comprehensive Loss

Comprehensive loss is defined as the change in equity of a company during a period from transactions and other events and circumstances excluding transactions resulting from distributions to owners. There was no difference from reported net loss for the years ended December 31, 2016, 2015 and 2014.

Revenue Recognition

Revenue is recognized when persuasive evidence of an arrangement exists, title or risk of loss has passed, the selling price is fixed or determinable and collection is reasonably assured. Products are sold through direct sales or medical device distributors and revenue is recognized upon sale to a bariatric center of excellence or a medical device distributor when no right of return or price protection exists. Terms of sales to international distributors are generally EXW, reflecting that goods are shipped “ex works,” in which risk of loss is assumed by the distributor at the shipping point. A provision for returns is recorded only if product sales provide for a right of return. No provision for returns was recorded for the years ended December 31, 2015 and December 31, 2016, as the product sales recorded did not provide for rights of return.

Research and Development Expenses

Research and development expenses are charged to expense as incurred. Research and development expenses include, but are not limited to, product development, clinical trial expenses, including supplies, devices, explants and revisions, quality assurance, regulatory expenses, payroll and other personnel expenses, materials and consulting costs.

Patent Costs

Costs associated with the submission of a patent application are expensed as incurred given the uncertainty of the patents resulting in probable future economic benefits to the Company. Patent-related legal expenses included in general and administrative costs were $269,000, $200,000, and $338,000 for the years ended December 31, 2016, 2015 and 2014, respectively.

Stock-Based Compensation

The fair value method is applied to all share-based payment awards issued to employees and where appropriate, nonemployees, unless another source of literature applies. When determining the measurement date of a nonemployee’s share-based payment award, the Company measures the stock options at fair value and remeasures such stock options to the current fair value until the performance date has been reached. All option grants are expensed on a straight-line basis over the vesting period.

Net Loss Per Share

Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is based on the weighted-average common shares outstanding during the period plus dilutive potential common shares calculated using the treasury stock method. Such potentially dilutive shares are excluded when the effect would be to reduce a net loss per share. The Company’s potential dilutive shares, which include outstanding common stock options and warrants, have not been included in the computation of diluted net loss per share for all periods as the result would be anti-dilutive.

The following table sets forth the computation of basic and diluted net loss per share for the years ended December 31, 2016, 2015 and 2014:


	Year Ended
	December 31,
	2016		2015		2014
Numerator:
Net loss	$	(23,360,844)	$	(25,498,747)	$	(26,128,720)
Denominator for basic and diluted net loss per share:
Weighted-average common shares outstanding		622,431		85,290		64,635
Net loss per share—basic and diluted	$	(37.53)	$	(298.97)	$	(404.25)

The following table sets forth the potential shares of common stock that are not included in the calculation of diluted net loss per share because to do so would be anti-dilutive as of the end of each period presented:


	December 31,
	2016	2015
Stock options outstanding	19,840	21,935
Warrants to purchase common stock	55,044	54,875

Recently Issued Accounting Standards

In April 2015, the Financial Accounting Standards Board (FASB) issued Simplifying the Presentation of Debt Issuance Costs, (Accounting Standards Update No. 2015-03 (ASU 2015-03)), which changes the presentation of debt issuance costs in the financial statements. Under ASU 2015-03, an entity presents such costs in the balance sheet as a direct deduction from the recognized debt liability rather than as an asset. Amortization of the costs is reported as interest expense. This guidance was effective for interim and annual reporting periods beginning after December 15, 2015. The new guidance did not have a material effect on the Company’s financial position, results of operations or cash flows.

In May 2014, FASB issued Revenue from Contracts with Customers, Topic 606 (Accounting Standards Update No. 2014-09 (ASU 2014-09)), which provides a framework for the recognition of revenue, with the objective that recognized revenues properly reflect amounts an entity is entitled to receive in exchange for goods and services. This guidance will be effective for interim and annual reporting periods beginning after December 15, 2017. The Company does not believe that the adoption of the new standard will have a material effect on its consolidated financial statements in that the accounting related to its current revenue-based business practices will not change under the new standard.

In August 2014, FASB issued Disclosure of Uncertainties About an Entity’s Ability to Continue as a Going Concern, (Accounting Standards Update No. 2014-15 (ASU 2014-15)), which provides a framework for entities to evaluate going concern issues as well as potential related disclosures. This guidance became effective and the Company adopted it for the year ended December 31, 2016. See Note 3, Liquidity and Management’s Plans.

In March 2016, FASB issued Improvements to Employee Share-Based Payment Accounting, (Accounting Standards Update No. 2016-09 (ASU 2016-09)), which is intended to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, the estimation of forfeitures, shares withheld for taxes and classification of shares withheld for taxes on the statement of cash flows. As part of the adoption of this guidance the Company has elected to account for forfeitures of share-based awards as they occur. The Company will adopt ASU 2016-09 as required on January 1, 2017 and the adoption will not have a material effect on its consolidated financial statements.

Various other accounting standards and interpretations have been issued with 2016 effective dates and effective dates subsequent to December 31, 2016. The Company has evaluated the recently issued accounting pronouncements that are currently effective or will be effective in 2016 and believe that none of them have had or will have a material effect on the Company’s financial position, results of operations or cash flows.

Liquidity and Management's Plans

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Liquidity and Management's Plans

(3)Liquidity and Management’s Plans

The accompanying consolidated financial statements have been prepared assuming the Company will continue as a going concern. The Company has financed its operations to date principally through the sale of equity securities, debt financing and interest earned on investments. As of December 31, 2016, the Company had $3.3 million of cash and cash equivalents to fund its operations into early 2017. On January 23, 2017, the Company received $19.0 million in gross proceeds, prior to deducting offering expenses of approximately $2.5 million, at the closing of an underwritten public offering of units in order to fund its operations (see Note 18, Subsequent Events).:

The following financing transactions occurred in 2015, 2016 and early 2017 to fund the Company’s operations:

On July 8, 2015, the Company closed a public offering of units consisting of common stock and the Series A Warrants. Gross proceeds of the offering were $16.0 million, prior to deducting offering expenses of approximately $1.4 million

On November 4, 2015 the Company entered into a securities purchase agreement (the Purchase Agreement) with institutional investors to issue up to $25.0 million of senior amortizing convertible notes (the Notes) and Note Warrants, in three separate closings. $1.5 million of the Notes was funded at the first closing on November 9, 2015 (the First Closing).

An additional $11.0 million of the Notes was funded at the second closing on January 11, 2016 (the Second Closing).

An additional $6.25 million of the Notes was funded at the third closing on May 2, 2016 (the Third Closing).

On January 23, 2017, the Company closed an underwritten public offering consisting of units of common stock, convertible preferred stock and warrants to purchase common stock. Gross proceeds of the offering were $19.0 million, prior to deducting underwriting discounts and commissions and offering expenses of approximately $2.5 million (see Note18, Subsequent Events).

Between January 1, 2017 and March 6, 2017, common stock warrants for 559,256 shares of common stock were exercised by warrant holders with proceeds to the Company of $3.1 million (see Note 18, Subsequent Events).

The Company’s anticipated operations include plans to expand the controlled commercial launch of vBloc Therapy, delivered via the vBloc System. The Company believes that it has the flexibility to manage the growth of its expenditures and operations depending on the amount of available cash flows. Additionally, the Company has evaluated its projected cash flows through March 2018 using the guidance of ASU 2014-15, Disclosure of Uncertainties About an Entity’s Ability to Continue as a Going Concern (ASC 205-40), and believes that its current available cash should enable it to sustain operations into March 2018. However, the Company will ultimately need to achieve sufficient revenues from product sales and/or obtain additional debt or equity financing to support its operations.

Fair Value Measurements

12 Months Ended

Dec. 31, 2016

Cash and Cash Equivalents [Abstract]

Fair Value Measurements

(4)Fair Value Measurements

Fair value of financial assets and liabilities is defined as the price that would be received to sell an asset or transfer a liability in an orderly transaction between market participants at the measurement date. A fair value hierarchy has been established that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below:

Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.

Level 2—Quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or model-derived valuations for which all significant inputs are observable, either directly or indirectly.

Level 3—Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable.

The Company did not hold any short-term investments classified as available for sale or held to maturity as of December 31, 2016 and 2015.

The fair value of the Company’s common stock warrant liability is calculated using a Black-Scholes valuation model and is classified as Level 2 in the fair value hierarchy. The fair values are presented below along with valuation assumptions:


		Series A Warrants						November 2015 Note Warrants
	December 31, 2016			December 31, 2015			December 31, 2016			December 31, 2015
Risk-free interest rates		1.20	%		0.91	%		1.47	%		1.75	%
Expected life		24	months		42	months		46	months		60	months
Expected dividends		—	%		—	%		—	%		—	%
Expected volatility		122.03	%		89.89	%		102.29	%		84.85	%
Fair value	$	36,000		$	2,759,583		$	449		$	118,234


		January 2016 Note Warrants						May 2016 Note Warrants
	December 31, 2016			January 11, 2016			December 31, 2016			May 2, 2016
Risk-free interest rates		1.93	%		1.58	%		1.93	%		1.32	%
Expected life		48	months		60	months		52	months		60	months
Expected dividends		—	%		—	%		—	%		—	%
Expected volatility		108.57	%		85.90	%		106.37	%		89.28	%
Fair value	$	1,633		$	515,157		$	1,037		$	150,195

The following table summarizes fair value measurements of the Note Warrants issued in 2016 by level at December 31, 2016:


	Level 1		Level 2		Level 3		Total
December 31, 2015
Senior amortizing convertible notes (net of discounts of $149,340)	$	—	$	—	$	1,267,182	$	1,267,182
Common stock warrants		—		2,877,817		—		2,877,817
Total December 31, 2015	$	—	$	2,877,817	$	1,267,182	$	4,144,999
December 31, 2016
Common stock warrants	$	—	$	39,119	$	—	$	39,119

During the year ended December 31, 2016 all the amounts outstanding under the Notes were paid off via conversions into shares of common stock.

As of December 31, 2015, the fair value of the outstanding Notes from the First Closing was determined to be $1.3 million. The fair value of the Notes issued with the Second Closing was determined to be $2.4 million on the January 11, 2016 issue date. The fair value of the Notes issued with the Third Closing was determined to be $6.0 million on the May 2, 2016 issue date. The fair values were calculated using a Binomial Lattice model and the following assumptions:


	November 2015 Notes				January 2016 Notes
	December 31, 2016		December 31, 2015		December 31, 2016		January 11, 2016
Risk-free interest rates	N/A		1.11	%	N/A		1.01	%
Expected life	N/A		1.86	years	N/A		1.83	years
Expected dividends	N/A		—	%	N/A		—	%
Expected volatility	N/A		57.5	%	N/A		60.0	%
Fair value per share of common stock	N/A	$	1.95		N/A	$	1.33


	May 2016 Notes
	December 31, 2016		May 2, 2016
Risk-free interest rates	N/A		0.69	%
Expected life	N/A		1.52	years
Expected dividends	N/A		—	%
Expected volatility	N/A		65.0	%
Fair value per share of common stock	N/A	$	0.80

For the years ended December 31, 2016 and December 31, 2015, respectively, the Company converted $20.3 million and $0.1 million of principal and interest of the Notes into shares of common stock. There were no gains or losses resulting from the Notes recognized in the consolidated statements of operations for the years ended December 31, 2016 or December 31, 2015.

Inventory

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Inventory

(5)Inventory

From inception, inventory related purchases had been used for research and development related activities and had accordingly been expensed as incurred. In December 2011, the Company began receiving Australian Register of Therapeutic Goods (ARTG) listings for components of the vBloc System from the Australian Therapeutic Goods Administration, with the final components being listed on the ARTG in January 2012. As a result, the Company determined certain assets were recoverable as inventory beginning in December 2011. The Company accounts for inventory at the lower of cost or market and records any long-term inventory as other assets in the consolidated balance sheets. There was approximately $676,000 and $519,000 of long-term inventory, primarily consisting of raw materials, as of December 31, 2016 and 2015, respectively.

Current inventory consists of the following as of:


	December 31,		December 31,
	2016		2015
Raw materials	$	335,606	$	576,898
Work-in-process		1,437,957		1,066,345
Finished goods		16,015		43,081
Inventory	$	1,789,578	$	1,686,324

Property and Equipment

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property and Equipment

(6)Property and Equipment

Property and equipment consists of the following as of:


	December 31,
	2016		2015
Furniture and equipment	$	2,302,878	$	2,299,290
Computer hardware and software		596,292		585,880
Leasehold improvements		62,651		62,651
		2,961,821		2,947,821
Less accumulated depreciation and amortization		(2,761,101)		(2,621,525)
Property and equipment, net	$	200,720	$	326,296

Accrued Expenses

12 Months Ended

Dec. 31, 2016

Payables and Accruals [Abstract]

Accrued Expenses

(7)Accrued Expenses

Accrued expenses consist of the following as of:


	December 31,
	2016		2015
Professional service related expenses	$	1,858,912	$	1,912,775
Payroll related expenses		507,327		1,270,208
Other expenses		385,176		412,432
Accrued expenses	$	2,751,415	$	3,595,415

Senior Amortizing Convertible Notes

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Senior Amortizing Convertible Notes

(8)Senior Amortizing Convertible Notes

On November 4, 2015, the Company entered into the Purchase Agreement to issue and sell to four institutional investors 7% senior amortizing convertible notes due 2017 in three separate closings. The Notes were initially convertible into shares of the Company’s common stock at a price equal to $304.50 per share with an aggregate principal amount of $25.0 million. Each Note was sold with Note Warrant with an exercise price of $325.50 per share. The Company issued and sold Notes and Note Warrants for aggregate total proceeds of $12.5 million in the First Closing and Second Closing and after entering into the First Amendment, which provided that the scheduled third closing would be split into two separate closings, issued and sold Notes and Note Warrants for aggregate total proceeds of $6.25 million in the Third Closing. After the Third Closing, the Company entered into the Second Amendment, which set a deadline of December 30, 2016 for the final closing and provided the consent of the holders of the Notes to the Company reducing the conversion price of the Notes from time to time in order to incentivize the holders of the Notes to convert their Notes into shares of the Company’s common stock. As the final closing did not occur prior to the December 30, 2016 deadline, the remaining $6.25 million of Notes was not funded. Additionally, after entering into the Second Amendment, the Company reduced the conversion price of the Notes frequently in order to incentivize the holders of the Notes to convert all of the outstanding amounts outstanding under the Notes. As of December 31, 2016, all of the Notes were fully repaid.

During the year ended December 31, 2016, $18.7 million of aggregate principal amount of Notes were converted by holders of the Notes into approximately 2,632,000 shares of the Company’s common stock.

Description of the Notes

The Notes were payable in monthly installments, accrued interest at a rate of 7.0% per annum from the date of issuance and had a maturity date 24 months after the First Closing. The Notes were repayable, at the Company’s election, in either cash or shares of the Company’s common stock at a discount to the then-current market price. The Notes were also convertible from time to time, at the election of the holders, into shares of the Company’s common stock at an initial conversion price of $304.50 per share. The conversion price was adjusted to $76.30 per share on January 29, 2016, the 16th trading day following the First Reverse Stock Split, per the terms of the Notes. The Notes also allowed the Company to reduce the conversion price from time-to-time, upon the holders’ consent, which was provided for in the Second Amendment.

The holder of each Note had the right to convert any portion of such Note unless the holder, together with its affiliates, beneficially owned in excess of 4.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to the conversion, as such percentage ownership was determined in accordance with the terms of the Notes. The holders were also able to increase or decrease such percentage to any other percentage, but in no event above 9.99%, provided that any increase of such percentage would not be effective until 61 days after providing notice to the Company.

The Company determined that the conversion feature in the Notes requires bifurcation and liability classification and measurement, at fair value, and requires evaluation at each reporting period. Under Accounting Standards Codification (ASC) 825, Financial Instruments, the FASB provides an alternative to bifurcation and companies may instead elect fair value measurement for the entire instrument, including the debt and conversion feature. The Company elected the fair value alternative in order to simplify its accounting and reporting of the Notes upon issuance. The fair value of the Note Warrants was recorded as a discount to the Notes and amortized to interest expense following the effective interest rate method over the term of the Notes.

The First Closing occurred on November 9, 2015. At the First Closing, the Company issued and sold Notes with an aggregate principal amount of $1.5 million, along with Note Warrants exercisable for 1,679 shares. During the quarter ended September 30, 2016, all remaining principal and interest amounts outstanding under the Notes issued at the First Closing were paid off via conversions to common shares.

The Second Closing occurred on January 11, 2016 after the Company received approval of the offering by the Company’s stockholders and the satisfaction of certain customary closing conditions. At the Second Closing, the Company issued and sold Notes with an aggregate principal amount of $11.0 million, along with Note Warrants exercisable for 12,312 shares. The fair value of Note Warrants issued on January 11, 2016 was determined to be $515,000 using a Black-Scholes valuation model. During the quarter ended December 31, 2016, all remaining principal and interest amounts outstanding under Notes issued at the Second Closing were paid off via conversions to common shares.

The Third Closing occurred on May 2, 2016 after the Company entered into the First Amendment and satisfied certain closing conditions. At the Third Closing, the Company issued and sold Notes with an aggregate principal amount of $6.25 million, along with Note Warrants exercisable for 6,995 shares. The fair value of the Note Warrants issued on May 2, 2016 was determined to be $150,195 using a Black-Scholes valuation model. During the quarter ended December 31, 2016, all remaining principal and interest amounts outstanding under Notes issued at the Third Closing were paid off via conversions to common shares.

On December 31, 2015, the fair value of the outstanding Notes was determined to be $1.3 million using a Binomial Lattice model.

The following table summarizes the installment amounts and additional conversions by the holders of the Notes through December 31, 2016:

First Closing:


							Common
	Principal		Interest		Total		Shares
Installment amount at December 31, 2015	$	65,217	$	23,651	$	88,868	814
Holder conversions during the quarter ended December 31, 2015		18,261		2,375		20,636	189
Total installments and conversions, December 31, 2015		83,478		26,026		109,504	1,003
Installment amount at February 29, 2016		65,217		23,681		88,898	1,314
Installment amount at March 31, 2016		65,217		14,827		80,044	1,271
Holder conversions during the quarter ended March 31, 2016		104,784		12,762		117,546	1,524
Total installments and conversions, March 31, 2016		318,696		77,296		395,992	5,112
Installment amount at April 30, 2016		65,217		13,853		79,070	1,454
Installment amount at May 31, 2016		65,217		13,082		78,299	2,121
Installment amount at June 30, 2016		54,217		11,275		65,492	3,590
Holder conversions during the quarter ended June 30, 2016		1,627		174		1,801	29
Total installments and conversions, June 30, 2016		504,974		115,680		620,654	12,306
Installment amount at July 31, 2016		65,217		10,148		75,365	5,521
Installment amount at August 31, 2016		46,957		5,830		52,787	4,593
Holder conversions during the quarter ended September 30, 2016		882,852		78,634		961,486	72,528
Total installments and conversions, September 30, 2016 and December 31, 2016	$	1,500,000	$	210,292	$	1,710,292	94,948

Second Closing:


							Common
	Principal			Interest		Total	Shares

Installment amount at March 2, 2016	$	404,762	$	149,300	$	554,062	*
Holder conversions during the quarter ended March 31, 2016		987,000		124,050		1,111,050	14,974
Total installments and conversions, March 31, 2016		1,391,762		273,350		1,665,112	14,974
Installment amount at April 29, 2016		404,762		149,497		554,259	10,190
Installment amount at May 31, 2016		291,428		86,518		377,946	10,238
Installment amount at June 30, 2016		404,762		82,913		487,675	22,842
Holder conversions during the quarter ended June 30, 2016		25,373		2,995		28,368	414
Total installments and conversions, June 30, 2016		2,518,087		595,273		3,113,360	58,658
Installment amount at July 31, 2016		213,429		47,457		260,886	19,113
Installment amount at August 31, 2016		631,429		116,511		747,940	64,810
Installment amount at September 30, 2016		404,762		45,846		450,608	51,698
Holder conversions during the quarter ended September 30, 2016		4,868,679		418,847		5,287,526	418,253
Total installments and conversions, September 30, 2016		8,636,386		1,223,934		9,860,320	612,532
Installment amount at Oct 31, 2016		340,000		24,738		364,738	70,665
Installment amount at Nov 30, 2016		291,429		27,528		318,957	81,952
Installment amount at December 31, 2016		156,867		11,425		168,292	57,453
Holder conversions during the quarter ended December 31, 2016		1,575,318		122,624		1,697,942	450,385
Total installments and conversions, December 31, 2016	$	11,000,000	$	1,410,249	$	12,410,249	1,272,987

Third Closing


							Common
		Principal		Interest		Total	Shares

Installment amount at June 30, 2016	$	212,158	$	90,659	$	302,817	16,600
Holder conversions during the quarter ended June 30, 2016		—		—		—	—
Total installments and conversions, June 30, 2016		212,158		90,659		302,817	16,600
Installment amount at July 31, 2016		147,368		32,374		179,742	13,168
Cash Payment – July 31, 2016 installment		42,105		6,107		48,212	*
Installment amount at August 31, 2016		336,842		62,059		398,901	34,684
Installment amount at September, 2016		263,158		41,822		304,980	34,523
Holder conversions during the quarter ended September 30, 2016		1,915,698		175,092		2,090,790	155,272
Total installments and conversions, September 30, 2016		2,917,329		408,113		3,325,442	254,247
Installment amount at Oct 31, 2016		221,053		35,004		256,057	48,192
Installment amount at Nov 30, 2016		221,053		31,259		252,312	64,828
Installment amount at December 31, 2016		221,053		14,526		235,579	81,872
Holder conversions during the quarter ended December 31, 2016		2,669,512		170,359		2,839,871	816,707
Total installments and conversions, December 31, 2016	$	6,250,000	$	659,261	$	6,909,261	1,265,846

* Cash payments

Description of the Note Warrants

Each Note Warrant is exercisable immediately and for a period of 60 months from the date of the issuance of the Note Warrant. After completion of the Third Closing, the Note Warrants entitle their holders to purchase, in aggregate, 27,982 shares of the Company’s common stock. The Note Warrants were initially exercisable at an exercise price equal to $325.50, subject to adjustment on the eighteen month anniversary of issuance, and certain other adjustments. The exercise price and number of shares of common stock issuable on the exercise of the Note Warrants is subject to adjustment upon the issuance of any shares of common stock or securities convertible into shares of common stock below the then-existing exercise price, with certain exceptions. Additionally, the exercise price and number of shares of common stock issuable upon the exercise of the Note Warrants are subject to adjustment in the event of any stock split, reverse stock split, recapitalization, reorganization or similar transaction. The holder of each Note Warrant does not have the right to exercise any portion of such Note Warrant if the holder, together with its affiliates, beneficially owns in excess of 4.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the Note Warrants. However, any holder may increase or decrease such percentage to any other percentage, but in no event above 9.99%, provided that any increase of such percentage will not be effective until 61 days after providing notice to the Company.

The exercise price of the Note Warrants issued November 9, 2015 was reduced to $76.30 per share on January 29, 2016, the 16th trading day following the First Reverse Stock Split, per the terms of the Note Warrants. Per the terms of the Note Warrants, the exercise price of each of the Note Warrants issued January 11, 2016 and May 2, 2016 remained $325.50 until January 20, 2017, the 16th trading day following the Second Reverse Stock Split, at which point the price of all of the Note Warrants was adjusted to $2.18 per share. All of the Note Warrants remain subject to adjustment on the eighteen month anniversary of issuance.

Preferred Stock	12 Months Ended
Preferred Stock	Dec. 31, 2016
Equity [Abstract]
Preferred Stock	(9)Preferred Stock The Company’s Sixth Amended and Restated Certificate of Incorporation currently authorizes 5,000,000 shares of $0.01 par value preferred stock. As of December 31, 2016 and 2015, there were no shares of preferred stock issued or outstanding. On January 23, 2017, the Company closed an underwritten public offering that included 12,531 shares of convertible preferred stock. On January 23 and January 24, 2017 all shares of preferred stock issued in conjunction with the offering were converted by their holders into 2,359,894 shares of common stock. See Note 18, Subsequent Events.

Stock Sales	12 Months Ended
Stock Sales	Dec. 31, 2016
Text Block [Abstract]
Stock Sales	(10)Stock Sales Sales Agreement—July 2015 On July 8, 2015, the Company closed a public offering, where it sold 30,476 units at an aggregate price of $525.00 per unit, for gross proceeds of $16.0 million before deducting estimated offering expenses of approximately $1.4 million, of which $532,000 was assigned to the warrants issued with each unit sold and was recognized immediately as interest expense in the consolidated statements of operations as the warrants are exercisable upon issuance. Each unit consisted of: (A)(i) one share of common stock or (ii) one pre-funded Series C warrant to purchase one share of common stock at an exercise price equal to $525.00 per share (Series C Warrant); and (B) one Series A Warrant with an exercise price initially equal to $630.00 per share (Series A Warrant). Each purchaser of a unit could elect to receive a Series C Warrant in lieu of a share of common stock. No Series C Warrants were issued. The Series A Warrants are exercisable for a period of 42 months from the closing date of the public offering. The exercise price and number of shares of common stock issuable on the exercise of the Series A Warrants are subject to adjustment upon the issuance of any shares of common stock or securities convertible into shares of common stock below the then-existing exercise price, with certain exceptions, and in the event of any stock split, reverse stock split, recapitalization, reorganization or similar transaction. The holder of the Series A Warrant does not have the right to exercise any portion of the Series A Warrant if the holder, together with its affiliates, would, subject to certain limited exceptions, beneficially own in excess of 9.99% of the Company’s common stock outstanding immediately after the exercise or 4.99% as may be elected by the purchaser. The exercise price of the Series A Warrants issued July 8, 2015 was reduced to $168.00 per share on November 9, 2015 as a result of the issuance of the Notes and was further reduced to $67.90 per share on January 29, 2016, the 16th trading day following the First Reverse Stock Split, per the terms of the Series A Warrants and was further reduced at various times during the year ended December 31, 2016 as a result of installment and acceleration payments made on the Notes. As of December 31, 2016, the exercise price of the warrants was $2.80 per share and on January 20, 2017, the 16th trading day following the Second Reverse Stock Split, the exercise price of the Series A Warrants was adjusted to $2.18 per share, per the terms of the Series A Warrants. Sales Agreement—June 2014 On June 13, 2014, the Company entered into a sales agreement with Cowen and Company, LLC (Cowen) to sell shares of the Company’s common stock having aggregate gross sales proceeds of up to $25.0 million, from time to time, through an at-the-market (ATM) facility under which Cowen will act as the Company’s sales agent (the Cowen ATM). The Company will determine, at its sole discretion, the timing and number of shares to be sold under the Cowen ATM. The Company will pay Cowen a commission for its services in acting as agent in the sale of common stock equal to 3.0% of the gross sales price per share of all shares sold through it as agent under the sales agreement. As of December 31, 2015, the Company had sold 5,256 shares under the Cowen ATM at a weighted-average selling price of $1,442.00 per share for gross proceeds of $7.6 million before deducting offering expenses. There have been no shares sold under the Cowen ATM subsequent to December 31, 2015 through March 6, 2017. The Company can direct Cowen to sell up to $17.4 million in common stock, provided we remain in compliance with all of the conditions under the Cowen ATM.

Income Taxes

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

(11)Income Taxes

The Company has incurred net operating losses (NOLs) since inception. The Company has not reflected any benefit of such net operating loss carryforwards in the accompanying consolidated financial statements.

The income tax expense benefit differed from the amount computed by applying the U.S. federal income tax rate of 34% to income before income taxes as a result of the following:


	2016		2015		2014
Computed ‘expected’ tax benefit	34	%	34	%	34	%
Other permanent adjustments	3.1	%	1.6	%	(2.3)	%
Research and development credit	0.6	%	0.9	%	0.3	%
Federal valuation allowance	(37.7)	%	(36.5)	%	(32)	%
	—	%	—	%	—	%

The tax effect of temporary differences that give rise to significant portions of the deferred tax assets as of December 31 is presented below:


	2016		2015
Deferred tax assets (liabilities):
Start-up costs	$	6,662,000	$	8,886,000
Capitalized research and development costs		23,012,000		29,781,000
Reserves and accruals		8,933,000		8,121,000
Property and equipment		83,000		107,000
Research and development credit		2,198,000		1,972,000
Net operating loss carryforwards		41,657,000		25,695,000
Total gross deferred tax assets		82,545,000		74,562,000
Valuation allowance		(82,545,000)		(74,562,000)
Net deferred tax assets	$	—	$	—

In assessing the realization of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during periods in which those temporary differences become deductible. In addition, certain limitations imposed under the Internal Revenue Code (IRC) could further limit the Company’s realization of these deferred tax assets in the event of changes in ownership of the Company, as defined by IRC Section 382. Based on the level of historical taxable losses and projections of future taxable income (losses) over the periods in which the deferred tax assets can be realized, management currently believes that it is more likely than not that the Company will not realize the benefits of these deductible differences. Accordingly, the Company has provided a valuation allowance against the gross deferred tax assets as of December 31, 2016 and 2015.

The Company’s ability to utilize its net operating loss carryforwards and built-in items of deduction, including capitalized start-up costs and research and development costs, may be substantially limited due to ownership changes that may have occurred or that could occur in the future. These ownership changes may limit the amount of net operating loss carryforwards and built-in items of deduction that can be utilized annually to offset future taxable income. In general, an ownership change, as defined in IRC Section 382, results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50% of the outstanding stock of a company by certain stockholders or public groups. During 2011, the Company completed an IRC Section 382 review and the results of the review indicated that ownership changes had occurred. While the Company has not completed an IRC Section 382 review since 2011, it believes that it is likely that additional ownership changes have occurred since then. Since the Company has experienced an ownership change, utilization of carryforward attributes are subject to an annual limitation, which is determined by first multiplying the value of the Company’s common stock at the time of the ownership change by the applicable long-term, tax-exempt rate, and then could be subject to additional adjustments, as required. Any such limitation may result in the expiration of a significant portion of the carryforward attributes before utilization and the permanent loss of built-in items of deduction. Any carryforward attributes that expire prior to utilization or permanent loss of built-in items of deduction as a result of such limitations will be removed from deferred tax assets with a corresponding adjustment to the valuation allowance.

As of December 31, 2016, the Company has generated U.S. federal net operating loss carryforwards of approximately $161.4 million. Of the total federal net operating loss, $48.0 million will expire unused as a result of the 2011 Section 382 limitation and $221,000 are generated from excess tax benefits not yet recorded to the income tax payable, such that they are not reflected in the deferred tax asset balance. The federal net operating loss carryforwards expire in the years 2022 through 2036. The Company’s research and development credit carryforwards, if not used, begin to expire in 2024.

Net operating loss carryforwards of the Company are subject to review and possible adjustment by the taxing authorities. With certain exceptions (e.g. the net operating loss carryforwards), the Company is no longer subject to U.S. federal, state or local examinations by tax authorities for years prior to 2013. There are no tax examinations currently in progress.

Stock Options

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Options

(12)Stock Options

The Company has adopted the Second Amended and Restated 2003 Stock Incentive Plan (the Plan) that includes both incentive stock options and nonqualified stock options to be granted to employees, officers, consultants, independent contractors, directors and affiliates of the Company. At December 31, 2016 and 2015, according to the Plan 40,000,000 and 18,857 shares, respectively, were authorized and reserved. Pursuant to the terms of the Plan, the shares authorized under the Plan were not adjusted automatically as part of the Second Reverse Stock Split. Instead, pursuant to the terms of the Plan, the board of directors exercised its power to adjust the number of shares authorized under the Plan as it determines is necessary after a stock split or other similar event to prevent dilution or enlargement of the benefits intended to be made available under the Plan. On February 8, 2017, pursuant to the terms of the Plan, the board of directors adjusted the number of shares authorized under the Plan to 3,000,000 shares as a result of the recapitalization of the Company consisting of the Second Reverse Stock Split and the public offering of the Company’s stock which closed on January 23, 2017. Pursuant to the terms of the Plan, the board of directors is required to adjust the number of shares authorized under the Plan as it determines necessary after a recapitalization or other similar corporate transaction to prevent dilution or enlargement of the benefits or potential benefits intended to be made available under the Plan.

The board of directors establishes the terms and conditions of all stock option grants, subject to the Plan and applicable provisions of the IRC. Incentive stock options must be granted at an exercise price not less than the fair market value of the common stock on the grant date. The options granted to participants owning more than 10% of the Company’s outstanding voting stock must be granted at an exercise price not less than 110% of fair market value of the common stock on the grant date. The options expire on the date determined by the board of directors, but may not extend more than 10 years from the grant date, while incentive stock options granted to participants owning more than 10% of the Company’s outstanding voting stock expire five years from the grant date. The vesting period for employees is generally over four years. The vesting period for nonemployees is determined based on the services being provided.

Stock option activity for the Plan is as follows:


		Outstanding Options

	Shares				Aggregate
	Available For	Number of	Weighted-Average		Intrinsic
	Grant	Shares	Exercise Price		Value
Balance, December 31, 2013	519	11,129	$	2,660.00
Shares reserved	7,143	—		—
Options granted	(1,197)	1,197		1,712.00
Options exercised	—	—		—
Options cancelled	275	(275)		2,528.00

Balance, December 31, 2014	6,740	12,051		2,597.00	$	519,546
Shares reserved	—	—
Options granted	(3,238)	3,238		1,104.00
Options exercised	—	—
Options cancelled	735	(735)		1,942.00

Balance, December 31, 2015	4,237	14,554		2,298.00
Shares reserved (1)	2,976,486	—		—
Options granted	(2,174)	2,174		45.35
Options exercised	—	—		—
Options cancelled	9,694	(9,694)		2,134.47

Balance, December 31, 2016	2,988,243	7,034	$	1,824.87	$	—

(1)Reflects the board of directors’ February 8, 2017 adjustment of number of shares reserved under the Plan from 40,000,000 to 3,000,000.

On June 27, 2016 the Company completed an option exchange offer to its employees whereby certain outstanding options to purchase shares of the Company’s common stock were tendered by employees in exchange for new options with the exercise price to be set at the then current market price of the Company’s common stock. Options to purchase 6,424 shares of the Company’s common stock, which included all the options eligible for exchange, were tendered by employees and cancelled by the Company. On the same date, options to purchase 1,083 shares of the Company’s common stock were issued with an exercise price of $23.28 per share, which was the Company’s closing stock price on June 27, 2016. Because the fair value of the tendered options immediately before the exchange approximated the fair value of the new options granted, no additional compensation expense was recognized.

In addition to the stock options granted pursuant to the Plan, the Company from time to time grants options to individuals as an inducement to accepting management positions (Inducement Grants). These Inducement Grants are made at the discretion of the board of directors and our issued outside of the Plan. Inducement Grants are summarized below:


		Outstanding Options

	Shares				Aggregate
	Available For	Number of	Weighted-Average		Intrinsic
	Grant	Shares	Exercise Price		Value
Balance, December 31, 2014	—	—		—
Shares reserved	7,380	—
Options granted	(7,380)	7,380	$	262.50
Options exercised	—	—
Options cancelled	—	—		—

Balance, December 31, 2015	—	7,380		262.50	$	—
Shares reserved	5,426	—		—
Options granted	(5,426)	5,426		94.05
Options exercised	—	—		—
Options cancelled	—	—		—

Balance, December 31, 2016	—	12,806	$	191.12	$	—

Each of the Inducement Grants will vest as follows: 25% of the shares will vest as of one year from the date of the officer’s employment agreement, and the remaining 75% of the shares will then vest in equal 2.0833% installments each month thereafter for 36 months. The options awarded as Inducement Grants were not eligible for the option exchange program

The options outstanding, vested and currently exercisable for the Plan and Inducement Grants are set forth by exercise price at December 31, 2016 in the following table:


	Outstanding Options and Expected to Vest				Options Exercisable and Vested
		Weighted-Average
	Number of	Remaining	Aggregate					Aggregate
Exercise	Shares	Contractual Life	Intrinsic		Number of	Weighted-Average		Intrinsic
Price	Outstanding	(Years)	Value		Options	Exercise Price		Value
$0.01 to $25.00	829	9.5	$	—	498	$	23.12	$	—
$25.01 to $175.00	6,416	9.1		—	846		72.56		—
$175.01 to $350.00	7,644	8.8		—	2,407		260.78		—
$350.01 to $1,475.00	2,073	7.2		—	2,041		1,321.12		—
> $1,475.00	2,878	5.1		—	2,870		3,460.40		—
	19,840		$	—	8,662	$	1,538.71	$	—

Stock-Based Compensation for Nonemployees

Stock-based compensation expenses related to stock options granted to nonemployees is recognized as the stock options are earned. The Company believes that the fair value of the stock options is more reliably measurable than the fair value of the services received. The fair value of the stock options granted is calculated at each reporting date, using the Black-Scholes option-pricing model, until the award vests or there is a substantial disincentive for the nonemployee not to perform the required services. The fair value for the years ended December 31, 2015 and 2014 was calculated using the following assumptions, defined below:


	Year Ended December 31,

	2016	2015	2014
Risk-free interest rates	N/A	0.02%–2.10%	0.08%–2.63%
Expected life	N/A	0.08 years–8.51 years	0.50 years–9.51 years
Expected dividends	N/A	0%	0%
Expected volatility	N/A	37.36%–132.01%	56.54%–139.65%

Stock-based compensation expense charged to operations on options granted to nonemployees for the years ended December 31, 2016, 2015 and 2014 was $3,535, $(34,712) and $181,323, respectively.

Employee Stock-Based Awards

Compensation cost for employee stock-based awards is based on the estimated grant-date fair value and is recognized over the vesting period of the applicable award on a straight-line basis. The weighted average estimated fair value of the employee stock options granted for the years ended December 31, 2016, 2015 and 2014 was $60.00, $426.30, and $1,486.00 per share, respectively.

The Company uses the Black-Scholes pricing model to determine the fair value of stock options. The determination of the fair value of stock-based payment awards on the date of grant is affected by the Company’s stock price as well as assumptions regarding a number of complex and subjective variables. These variables include the Company’s expected stock price volatility over the term of the awards, actual and projected employee stock option exercise behaviors, risk-free interest rates and expected dividends. The estimated grant-date fair values of the employee stock options were calculated using the Black-Scholes valuation model, based on the following assumptions for the years ended December 31, 2016, 2015 and 2014:


	Year Ended December 31,

	2016	2015	2014
Risk-free interest rates	0.87%–1.64%	1.49%–1.80%	1.73%–1.96%
Expected life	4.0 years–6.25 years	5.50 years–6.25 years	6.00 years–6.25 years
Expected dividends	0%	0%	0%
Expected volatility	88.43%–114.38%	83.36%–111.77%	118.64%–120.70%

Expected Life. The expected life is based on the “simplified” method described in the SEC Staff Accounting Bulletin, Topic 14: Share-Based Payment.

Volatility. The expected volatility was based on the Company’s historical volatility.

Risk-Free Interest Rate. The risk-free rate is based on the daily yield curve rate from the U.S. Treasury with remaining terms similar to the expected term on the options.

Dividend Yield. The Company has never declared or paid any cash dividends and does not plan to pay cash dividends in the foreseeable future, and, therefore, used an expected dividend yield of zero in the valuation model.

Forfeitures. The Company is required to estimate forfeitures at the time of grant, and revise those estimates in subsequent periods if actual forfeitures differ from those estimates. The Company uses historical data to estimate pre-vesting option forfeitures and record stock-based compensation expense only for those awards that are expected to vest. All stock-based payment awards are amortized on a straight-line basis over the requisite service periods of the awards, which are generally the vesting periods. If the Company’s actual forfeiture rate is materially different from its estimate, the stock-based compensation expense could be significantly different from what the Company has recorded in the current period.

As of December 31, 2016 there was approximately $2.8 million of total unrecognized compensation costs, net of estimated forfeitures, related to employee unvested stock option awards, which are expected to be recognized over a weighted-average period of 2.2 years.

There were no stock option exercises for the years ended December 31, 2016, 2015 and 2014.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Warrants

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Warrants

(13)Warrants

Stock warrant activity is as follows:


		Weighted
		Average
	Common	Exercise
	Shares	Price
Balance, December 31, 2013	24,331	$	1,964.90
Granted	—		—
Exercised	(1,265)		1,772.40
Cancelled	(22)		50,988.00
Balance, December 31, 2014	23,044		1,929.20
Granted (1)	32,155		116.20
Exercised	—		—
Cancelled	(324)		2,299.50
Balance, December 31, 2015	54,875		1,929.20
Granted (1)	19,308		325.50
Exercised	(1,428)		3.50
Cancelled	(17,706)		2,257.50
Balance, December 31, 2016	55,049	$	238.90

(1)See Notes 8 and 10 for discussions relating to the issuance of warrants in 2016 and 2015.

At December 31, 2016 and 2015, the weighted-average remaining contractual life of outstanding warrants was 2.76 and 2.18 years, respectively. All of the warrants outstanding are currently exercisable at the option of the holder into the equivalent number of shares of common stock.

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	(14)Related Party Transactions . Consulting Agreement—Anthony Jansz The Company entered into a consulting agreement with Anthony Jansz, who is a former member of the board of directors, for the period from June 1, 2011 through April 30, 2015. In exchange for consulting services provided, Mr. Jansz was entitled to receive consulting fees and options to purchase 16,663 shares of common stock at a weighted average exercise price of $29.78. Total stock-based compensation expense recorded was approximately $600 and $40,000 for the years ended December 31, 2015 and 2014, respectively. Due to a failure to meet certain performance conditions, 471 shares of the options granted to Mr. Jansz did not vest. In addition to the option grants, the Company paid Mr. Jansz approximately $75,000 and $196,000 in fees and expenses for consulting services provided during the years ended December 31, 2015 and 2014, respectively. No consulting fees or expenses were paid to Mr. Jansz in 2016. Consulting Agreement—Jon Tremmel Effective August 10, 2015, the Company entered into a one year consulting agreement with Jon Tremmel & Associates, LLC, which is wholly-owned by Jon Tremmel, a member of the board of directors. In exchange for consulting services provided, Mr. Tremmel was entitled to receive consulting fees and an option to purchase 16,666 shares of common stock at $3.45 per share. Total stock-based compensation expense recorded was approximately $3,000 and $13,000 for the years ended December 31, 2016 and 2015, respectively. In addition to the option grant, the Company paid Mr. Tremmel approximately $50,000 in fees and expenses for consulting services provided during the year ended December 31, 2015. No consulting fees or expenses were paid to Mr. Tremmel in 2016. Other The Company entered into an agreement with an advisory firm to provide various consulting services. The advisory firm is partially owned by a company with whom a member of our board of directors is a partner. The Company recognized $253,000 in selling, general and administrative expense for the year ended December 31, 2014 for consulting services provided by the advisory firm.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

(15)Commitments and Contingencies

Operating Lease

The Company rents its office, warehouse and laboratory facilities under an operating lease, which was originally set to expire on September 30, 2015. On August 25, 2015, the Company entered into an amendment extending the term of the operating lease for three years until September 30, 2018, with monthly base rent ranging from $18,925 to $20,345. Total rent expense recognized for the years ended December 31, 2016, 2015 and 2014, respectively, was $229,000, $262,000 and $271,000. Facility related expenses are included as general and administrative costs on the consolidated statements of operations.

The following is a schedule of total future minimum lease payments due as of December 31, 2016:


Year ending December 31,
2017	$	237,749
2018		183,103
	$	420,852

Product Liability Claims

The Company is exposed to product liability claims that are inherent in the testing, production, marketing and sale of medical devices. Management believes any losses that may occur from these matters are adequately covered by insurance, and the ultimate outcome of these matters will not have a material effect on the Company’s financial position or results of operations. The Company is not currently a party to any litigation and is not aware of any pending or threatened litigation that could have a material adverse effect on the Company’s business, operating results or financial condition.

Clinical Trials

The Company is evaluating the vBloc System in human clinical trials, including the EMPOWER trial and ReCharge trial. Both of these clinical trials require patients to be followed out to 60 months. The Company is required to pay for patient follow up visits only to the extent they occur. In the event a patient does not attend a follow up visit, the Company has no financial obligation. The Company is also required to pay for explants or revisions, including potential conversions of ReCharge control devices to active devices, should a patient request or be required to have one during the course of the clinical trials. The Company has no financial obligation unless an explant, revision or conversion is requested or required. Clinical trial costs are expensed as incurred.

Litigation

On February 28, 2017, the Company received a class action and derivative complaint filed on February 24, 2017 in U. S. District Court for the District of Delaware by Vinh Du, one of the Company’s shareholders. The complaint names as defendants EnteroMedics, the board of directors and four members of our senior management, namely, Scott Youngstrom, Nick Ansari, Peter DeLange and Paul Hickey, and contains a purported class action claim for breach of fiduciary duty against the board of directors and derivative claims for breach of fiduciary duty against the board of directors and unjust enrichment against our senior management. The allegations in the complaint relate to the increase in the number of shares authorized for grant under our Second Amended and Restated 2003 Stock Incentive Plan (the “Plan”), which was approved by our shareholders at the Special Meeting of Shareholders held on December 12, 2016 (the “Special Meeting”), and to our subsequent grant of stock options on February 8, 2017, to the Company’s Directors and senior management to purchase an aggregate of 1,093,450 shares of our common stock (the “Option Grants”). In the complaint, the plaintiff contends that (i) the number of shares authorized for grant under the Plan, as adjusted by the board of directors after the Special Meeting for the subsequent recapitalization of the Company, resulted from an alleged breach of fiduciary duties by the board of directors, and (ii) our senior management was allegedly unjustly enriched by the subsequent Option Grants. The plaintiff seeks relief in the form of an order rescinding the Plan as approved by the shareholders at the Special Meeting, an order cancelling the Option Grants, and an award to plaintiff for his costs, including fees and disbursements of attorneys, experts and accountants. We believe the allegations in the complaint are without merit, and intend to defend the action vigorously.

Except as disclosed in the foregoing paragraph, the Company is not currently a party to any litigation and the Company is not aware of any pending or threatened litigation against it that could have a material adverse effect on the Company’s business, operating results or financial condition. The medical device industry in which the Company operates is characterized by frequent claims and litigation, including claims regarding patent and other intellectual property rights as well as improper hiring practices. As a result, the Company may be involved in various legal proceedings from time to time.

Retirement Plan	12 Months Ended
Retirement Plan	Dec. 31, 2016
Postemployment Benefits [Abstract]
Retirement Plan	(16)Retirement Plan The Company has a 401(k) profit-sharing plan that provides retirement benefits to employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations. The Company’s matching is at the discretion of the Company’s board of directors. For the years ended December 31, 2016, 2015 and 2014, the Company did not provide any matching of employees’ contributions.

Quarterly Data

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Quarterly Data

(17)Quarterly Data (unaudited)

The following table represents certain unaudited quarterly information for each of the eight quarters in the period ended December 31, 2016. In management’s opinion, this information has been prepared on the same basis as the audited consolidated financial statements and includes all the adjustments necessary to fairly state the unaudited quarterly results of operations (in thousands, except per share data).


	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter (1)
2016:
Revenue	$	72	$	276	$	297	$	142
Net loss	$	(7,409)	$	(4,995)	$	(6,522)	$	(4,434)
Basic and diluted net loss per share	$	(66.14)	$	(33.96)	$	(11.77)	$	(2.65)
2015:
Revenue	$	—	$	79	$	64	$	149
Net loss	$	(7,174)	$	(7,404)	$	(4,151)	$	(6,770)
Basic and diluted net loss per share	$	(103.56)	$	(104.48)	$	(41.92)	$	(66.70)

(1)The $2.4 million reduction in the 2016 fourth quarter net loss compared with the 2015 fourth quarter net loss reflects a $3.5 mllion decrease in operating expenses partially offset by a $0.6 million increase in interest expense and a $0.5 million increase in expenses from net changes in warrant liability and convertible note liability valuations.

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	(18) Subsequent Events On January 23, 2017, the Company closed an underwritten public offering consisting of units of common stock, convertible preferred stock and warrants to purchase common stock. Gross proceeds of the offering were $19.0 million, prior to deducting underwriting discounts and commissions and offering expenses of approximately $2.5 million. The offering was comprised of Class A Units, priced at a public offering price of $5.31 per unit, with each unit consisting of one share of common stock and one five-year warrant (each, a "2017 Warrant") to purchase one share of common stock with an exercise price of $5.84 per share, and Class B Units, priced at a public offering price of $1,000 per unit, with each unit comprised of one share of Series A Preferred Stock (the Preferred Stock), which was convertible into 188 shares of common stock, and 2017 Warrants to purchase 188 shares of common stock. The conversion price of the Preferred Stock issued in the transaction as well as the exercise price of the 2017 Warrants are fixed priced and do not contain any variable pricing features nor any price based anti-dilutive features apart from customary adjustments for splits and reverse splits of common stock. The Preferred Stock included a beneficial ownership limitation of 4.99%, but had no dividend preference (except to extent dividends are also paid on the common stock), liquidation preference or other preferences over common stock. The securities comprising the units were immediately separable were issued separately. A total of 1,218,107 shares of common stock, 12,531 shares of Preferred Stock convertible into 2,359,894 shares of common stock, and 2017 Warrants to purchase 3,577,994 shares of common stock were issued in the offering including the underwriters’ exercise of their over-allotment option to purchase 466,695 shares of common stock and 2017 Warrants to purchase an additional 466,695 shares of common stock. On January 23 and January 24, 2017 all shares of Preferred Stock issued in conjunction with the offering were converted by their holders into 2,359,894 shares of common stock. Between January 1, 2017 and March 6, 2017, common stock warrants for 559,256 shares of common stock were exercised by warrant holders with proceeds to the Company of $3.1 million.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Basis of Presentation

Use of Estimates

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany transactions and accounts have been eliminated in consolidation.

Concentration of Credit Risk

Fair Value of Financial Instruments

Common Stock Warrant Liability

Cash and Cash Equivalents

Short-Term Investments

Inventory

The Company accounts for inventory at the lower of cost or market and records any long-term inventory as other assets in the consolidated balance sheets.

Property and Equipment, Net

Impairment of Long-Lived Assets

Income Taxes

Medical Device Excise Tax

Comprehensive Loss

Revenue Recognition

Research and Development Expenses

Patent Costs

Stock-Based Compensation

Net Loss Per Share

The following table sets forth the computation of basic and diluted net loss per share for the years ended December 31, 2016, 2015 and 2014:


	Year Ended
	December 31,
	2016		2015		2014
Numerator:
Net loss	$	(23,360,844)	$	(25,498,747)	$	(26,128,720)
Denominator for basic and diluted net loss per share:
Weighted-average common shares outstanding		622,431		85,290		64,635
Net loss per share—basic and diluted	$	(37.53)	$	(298.97)	$	(404.25)


	December 31,
	2016	2015
Stock options outstanding	19,840	21,935
Warrants to purchase common stock	55,044	54,875

Recently Issued Accounting Standards

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Computation of Basic and Diluted Net Loss per Share


	Year Ended
	December 31,
	2016		2015		2014
Numerator:
Net loss	$	(23,360,844)	$	(25,498,747)	$	(26,128,720)
Denominator for basic and diluted net loss per share:
Weighted-average common shares outstanding		622,431		85,290		64,635
Net loss per share—basic and diluted	$	(37.53)	$	(298.97)	$	(404.25)

Antidilutive Securities


	December 31,
	2016	2015
Stock options outstanding	19,840	21,935
Warrants to purchase common stock	55,044	54,875

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Series A Warrants Fair Value Calculated Using Black-Scholes Valuation Model


	November 2015 Notes				January 2016 Notes
	December 31, 2016		December 31, 2015		December 31, 2016		January 11, 2016
Risk-free interest rates	N/A		1.11	%	N/A		1.01	%
Expected life	N/A		1.86	years	N/A		1.83	years
Expected dividends	N/A		—	%	N/A		—	%
Expected volatility	N/A		57.5	%	N/A		60.0	%
Fair value per share of common stock	N/A	$	1.95		N/A	$	1.33


	May 2016 Notes
	December 31, 2016		May 2, 2016
Risk-free interest rates	N/A		0.69	%
Expected life	N/A		1.52	years
Expected dividends	N/A		—	%
Expected volatility	N/A		65.0	%
Fair value per share of common stock	N/A	$	0.80

Summary of Fair Value Measurements of Senior Amortizing Convertible Notes and Common Stock Warrants


	Level 1		Level 2		Level 3		Total
December 31, 2015
Senior amortizing convertible notes (net of discounts of $149,340)	$	—	$	—	$	1,267,182	$	1,267,182
Common stock warrants		—		2,877,817		—		2,877,817
Total December 31, 2015	$	—	$	2,877,817	$	1,267,182	$	4,144,999
December 31, 2016
Common stock warrants	$	—	$	39,119	$	—	$	39,119

Warrants

Series A Warrants Fair Value Calculated Using Black-Scholes Valuation Model


		Series A Warrants						November 2015 Note Warrants
	December 31, 2016			December 31, 2015			December 31, 2016			December 31, 2015
Risk-free interest rates		1.20	%		0.91	%		1.47	%		1.75	%
Expected life		24	months		42	months		46	months		60	months
Expected dividends		—	%		—	%		—	%		—	%
Expected volatility		122.03	%		89.89	%		102.29	%		84.85	%
Fair value	$	36,000		$	2,759,583		$	449		$	118,234


		January 2016 Note Warrants						May 2016 Note Warrants
	December 31, 2016			January 11, 2016			December 31, 2016			May 2, 2016
Risk-free interest rates		1.93	%		1.58	%		1.93	%		1.32	%
Expected life		48	months		60	months		52	months		60	months
Expected dividends		—	%		—	%		—	%		—	%
Expected volatility		108.57	%		85.90	%		106.37	%		89.28	%
Fair value	$	1,633		$	515,157		$	1,037		$	150,195

Inventory (Tables)

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Current Inventory


	December 31,		December 31,
	2016		2015
Raw materials	$	335,606	$	576,898
Work-in-process		1,437,957		1,066,345
Finished goods		16,015		43,081
Inventory	$	1,789,578	$	1,686,324

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property and Equipment


	December 31,
	2016		2015
Furniture and equipment	$	2,302,878	$	2,299,290
Computer hardware and software		596,292		585,880
Leasehold improvements		62,651		62,651
		2,961,821		2,947,821
Less accumulated depreciation and amortization		(2,761,101)		(2,621,525)
Property and equipment, net	$	200,720	$	326,296

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2016

Payables and Accruals [Abstract]

Accrued Expenses


	December 31,
	2016		2015
Professional service related expenses	$	1,858,912	$	1,912,775
Payroll related expenses		507,327		1,270,208
Other expenses		385,176		412,432
Accrued expenses	$	2,751,415	$	3,595,415

Senior Amortizing Convertible Notes (Tables)

12 Months Ended

Dec. 31, 2016

First closing

Summary of Installment Amounts and Additional Conversions


							Common
	Principal		Interest		Total		Shares
Installment amount at December 31, 2015	$	65,217	$	23,651	$	88,868	814
Holder conversions during the quarter ended December 31, 2015		18,261		2,375		20,636	189
Total installments and conversions, December 31, 2015		83,478		26,026		109,504	1,003
Installment amount at February 29, 2016		65,217		23,681		88,898	1,314
Installment amount at March 31, 2016		65,217		14,827		80,044	1,271
Holder conversions during the quarter ended March 31, 2016		104,784		12,762		117,546	1,524
Total installments and conversions, March 31, 2016		318,696		77,296		395,992	5,112
Installment amount at April 30, 2016		65,217		13,853		79,070	1,454
Installment amount at May 31, 2016		65,217		13,082		78,299	2,121
Installment amount at June 30, 2016		54,217		11,275		65,492	3,590
Holder conversions during the quarter ended June 30, 2016		1,627		174		1,801	29
Total installments and conversions, June 30, 2016		504,974		115,680		620,654	12,306
Installment amount at July 31, 2016		65,217		10,148		75,365	5,521
Installment amount at August 31, 2016		46,957		5,830		52,787	4,593
Holder conversions during the quarter ended September 30, 2016		882,852		78,634		961,486	72,528
Total installments and conversions, September 30, 2016 and December 31, 2016	$	1,500,000	$	210,292	$	1,710,292	94,948

Second closing

Summary of Installment Amounts and Additional Conversions


							Common
	Principal			Interest		Total	Shares

Installment amount at March 2, 2016	$	404,762	$	149,300	$	554,062	*
Holder conversions during the quarter ended March 31, 2016		987,000		124,050		1,111,050	14,974
Total installments and conversions, March 31, 2016		1,391,762		273,350		1,665,112	14,974
Installment amount at April 29, 2016		404,762		149,497		554,259	10,190
Installment amount at May 31, 2016		291,428		86,518		377,946	10,238
Installment amount at June 30, 2016		404,762		82,913		487,675	22,842
Holder conversions during the quarter ended June 30, 2016		25,373		2,995		28,368	414
Total installments and conversions, June 30, 2016		2,518,087		595,273		3,113,360	58,658
Installment amount at July 31, 2016		213,429		47,457		260,886	19,113
Installment amount at August 31, 2016		631,429		116,511		747,940	64,810
Installment amount at September 30, 2016		404,762		45,846		450,608	51,698
Holder conversions during the quarter ended September 30, 2016		4,868,679		418,847		5,287,526	418,253
Total installments and conversions, September 30, 2016		8,636,386		1,223,934		9,860,320	612,532
Installment amount at Oct 31, 2016		340,000		24,738		364,738	70,665
Installment amount at Nov 30, 2016		291,429		27,528		318,957	81,952
Installment amount at December 31, 2016		156,867		11,425		168,292	57,453
Holder conversions during the quarter ended December 31, 2016		1,575,318		122,624		1,697,942	450,385
Total installments and conversions, December 31, 2016	$	11,000,000	$	1,410,249	$	12,410,249	1,272,987

Third closing

Summary of Installment Amounts and Additional Conversions


							Common
		Principal		Interest		Total	Shares

Installment amount at June 30, 2016	$	212,158	$	90,659	$	302,817	16,600
Holder conversions during the quarter ended June 30, 2016		—		—		—	—
Total installments and conversions, June 30, 2016		212,158		90,659		302,817	16,600
Installment amount at July 31, 2016		147,368		32,374		179,742	13,168
Cash Payment – July 31, 2016 installment		42,105		6,107		48,212	*
Installment amount at August 31, 2016		336,842		62,059		398,901	34,684
Installment amount at September, 2016		263,158		41,822		304,980	34,523
Holder conversions during the quarter ended September 30, 2016		1,915,698		175,092		2,090,790	155,272
Total installments and conversions, September 30, 2016		2,917,329		408,113		3,325,442	254,247
Installment amount at Oct 31, 2016		221,053		35,004		256,057	48,192
Installment amount at Nov 30, 2016		221,053		31,259		252,312	64,828
Installment amount at December 31, 2016		221,053		14,526		235,579	81,872
Holder conversions during the quarter ended December 31, 2016		2,669,512		170,359		2,839,871	816,707
Total installments and conversions, December 31, 2016	$	6,250,000	$	659,261	$	6,909,261	1,265,846

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Tax Rate Reconciliation


	2016		2015		2014
Computed ‘expected’ tax benefit	34	%	34	%	34	%
Other permanent adjustments	3.1	%	1.6	%	(2.3)	%
Research and development credit	0.6	%	0.9	%	0.3	%
Federal valuation allowance	(37.7)	%	(36.5)	%	(32)	%
	—	%	—	%	—	%

Deferred Tax Assets


	2016		2015
Deferred tax assets (liabilities):
Start-up costs	$	6,662,000	$	8,886,000
Capitalized research and development costs		23,012,000		29,781,000
Reserves and accruals		8,933,000		8,121,000
Property and equipment		83,000		107,000
Research and development credit		2,198,000		1,972,000
Net operating loss carryforwards		41,657,000		25,695,000
Total gross deferred tax assets		82,545,000		74,562,000
Valuation allowance		(82,545,000)		(74,562,000)
Net deferred tax assets	$	—	$	—

Stock Options (Tables)

12 Months Ended

Dec. 31, 2016

Summary of Stock Option Activity


		Outstanding Options

	Shares				Aggregate
	Available For	Number of	Weighted-Average		Intrinsic
	Grant	Shares	Exercise Price		Value
Balance, December 31, 2013	519	11,129	$	2,660.00
Shares reserved	7,143	—		—
Options granted	(1,197)	1,197		1,712.00
Options exercised	—	—		—
Options cancelled	275	(275)		2,528.00

Balance, December 31, 2014	6,740	12,051		2,597.00	$	519,546
Shares reserved	—	—
Options granted	(3,238)	3,238		1,104.00
Options exercised	—	—
Options cancelled	735	(735)		1,942.00

Balance, December 31, 2015	4,237	14,554		2,298.00
Shares reserved (1)	2,976,486	—		—
Options granted	(2,174)	2,174		45.35
Options exercised	—	—		—
Options cancelled	9,694	(9,694)		2,134.47

Balance, December 31, 2016	2,988,243	7,034	$	1,824.87	$	—

(1)Reflects the board of directors’ February 8, 2017 adjustment of number of shares reserved under the Plan from 40,000,000 to 3,000,000.

Options Outstanding Vested and Currently Exercisable by Exercise Price


	Outstanding Options and Expected to Vest				Options Exercisable and Vested
		Weighted-Average
	Number of	Remaining	Aggregate					Aggregate
Exercise	Shares	Contractual Life	Intrinsic		Number of	Weighted-Average		Intrinsic
Price	Outstanding	(Years)	Value		Options	Exercise Price		Value
$0.01 to $25.00	829	9.5	$	—	498	$	23.12	$	—
$25.01 to $175.00	6,416	9.1		—	846		72.56		—
$175.01 to $350.00	7,644	8.8		—	2,407		260.78		—
$350.01 to $1,475.00	2,073	7.2		—	2,041		1,321.12		—
> $1,475.00	2,878	5.1		—	2,870		3,460.40		—
	19,840		$	—	8,662	$	1,538.71	$	—

Nonemployees

Stock Option Valuation Assumptions


	Year Ended December 31,

	2016	2015	2014
Risk-free interest rates	N/A	0.02%–2.10%	0.08%–2.63%
Expected life	N/A	0.08 years–8.51 years	0.50 years–9.51 years
Expected dividends	N/A	0%	0%
Expected volatility	N/A	37.36%–132.01%	56.54%–139.65%

Stock Incentive Plan 2003

Summary of Stock Option Activity


		Outstanding Options

	Shares				Aggregate
	Available For	Number of	Weighted-Average		Intrinsic
	Grant	Shares	Exercise Price		Value
Balance, December 31, 2014	—	—		—
Shares reserved	7,380	—
Options granted	(7,380)	7,380	$	262.50
Options exercised	—	—
Options cancelled	—	—		—

Balance, December 31, 2015	—	7,380		262.50	$	—
Shares reserved	5,426	—		—
Options granted	(5,426)	5,426		94.05
Options exercised	—	—		—
Options cancelled	—	—		—

Balance, December 31, 2016	—	12,806	$	191.12	$	—

Employees Stock Option Plan

Stock Option Valuation Assumptions


	Year Ended December 31,

	2016	2015	2014
Risk-free interest rates	0.87%–1.64%	1.49%–1.80%	1.73%–1.96%
Expected life	4.0 years–6.25 years	5.50 years–6.25 years	6.00 years–6.25 years
Expected dividends	0%	0%	0%
Expected volatility	88.43%–114.38%	83.36%–111.77%	118.64%–120.70%

Warrants (Tables)

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Stock Warrants Activity


		Weighted
		Average
	Common	Exercise
	Shares	Price
Balance, December 31, 2013	24,331	$	1,964.90
Granted	—		—
Exercised	(1,265)		1,772.40
Cancelled	(22)		50,988.00
Balance, December 31, 2014	23,044		1,929.20
Granted (1)	32,155		116.20
Exercised	—		—
Cancelled	(324)		2,299.50
Balance, December 31, 2015	54,875		1,929.20
Granted (1)	19,308		325.50
Exercised	(1,428)		3.50
Cancelled	(17,706)		2,257.50
Balance, December 31, 2016	55,049	$	238.90

(1)See Notes 8 and 10 for discussions relating to the issuance of warrants in 2016 and 2015.

- Definition

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

+ References + Details

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Lease Payment

The following is a schedule of total future minimum lease payments due as of December 31, 2016:


Year ending December 31,
2017	$	237,749
2018		183,103
	$	420,852

Quarterly Data (Tables)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Quarterly Information


	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter (1)
2016:
Revenue	$	72	$	276	$	297	$	142
Net loss	$	(7,409)	$	(4,995)	$	(6,522)	$	(4,434)
Basic and diluted net loss per share	$	(66.14)	$	(33.96)	$	(11.77)	$	(2.65)
2015:
Revenue	$	—	$	79	$	64	$	149
Net loss	$	(7,174)	$	(7,404)	$	(4,151)	$	(6,770)
Basic and diluted net loss per share	$	(103.56)	$	(104.48)	$	(41.92)	$	(66.70)

Description of the Business; Risks and Uncertainties of the Business (Detail)		1 Months Ended	12 Months Ended
	Nov. 09, 2015 shares	Jan. 31, 2006 SFr / shares shares	Dec. 31, 2016 item entity $ / shares shares	Jan. 23, 2017 shares	Dec. 27, 2016 item shares	Jan. 06, 2016 shares	Dec. 31, 2015 $ / shares shares
Organization And Description Of Business [Line Items]
Number of legal entities \| entity			2
Common stock, shares outstanding			2,736,621				102,415
Common stock, par value \| $ / shares			$ 0.01				$ 0.01
Stock Issued (in shares)	27,982
Number of reverse stock splits \| item			2
Common stock, reverse split ratio \| item			0.0667		70.0000
Common stock authorized for issuance			300,000,000		300,000,000	150,000,000	13,333,333
Subsequent Event
Organization And Description Of Business [Line Items]
Common stock, shares outstanding				1,218,107
Alpha Medical, Inc.
Organization And Description Of Business [Line Items]
Ownership percentage of an entity combined to form the Company			100.00%
Beta Medical, Inc.
Organization And Description Of Business [Line Items]
Ownership percentage of an entity combined to form the Company			100.00%
EnteroMedics Europe
Organization And Description Of Business [Line Items]
Common stock, shares outstanding		20
Common stock, par value \| SFr / shares		SFr 1,000
Repurchased shares percentage		100.00%
Stock Issued (in shares)		1

Summary of Significant Accounting Policies (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Significant Accounting Policies [Line Items]
Cash equivalents maturity period	90 days
Excise tax rate on medical devices	2.30%
Provision for returns	$ 0	$ 0
Patent related legal expenses	269,000	200,000	$ 338,000
Derivative instruments outstanding	$ 0	0	$ 0
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Short term investment maturity period	3 months
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Short term investment maturity period	1 year
Operating Expense
Schedule Of Significant Accounting Policies [Line Items]
Medical device tax		$ 1,363
Furniture and Fixtures \| Minimum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	5 years
Furniture and Fixtures \| Maximum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	7 years
Computer hardware and software \| Minimum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	3 years
Computer hardware and software \| Maximum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	5 years
Money Market Funds
Schedule Of Significant Accounting Policies [Line Items]
Money market funds preserve the value of investment per share	$ 1.00

Summary of Significant Accouting Policies - Computation of Basic and Diluted Net Loss Per Share (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net loss	$ (4,434,000)	$ (6,522,000)	$ (4,995,000)	$ (7,409,000)	$ (6,770)	$ (4,151)	$ (7,404)	$ (7,174)	$ (23,360,844)	$ (25,498,747)	$ (26,128,720)
Denominator for basic and diluted net loss per share:
Weighted-average common shares outstanding									622,431	85,290	64,635
Net loss per share-basic and diluted	$ (2.65)	$ (11.77)	$ (33.96)	$ (66.14)	$ (66.70)	$ (41.92)	$ (104.48)	$ (103.56)	$ (37.53)	$ (298.97)	$ (404.25)

Summary of Significant Accouting Policies - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Stock option outstanding
Anti-dilutive Securities
Anti-dilutive as of end of each period	19,840	21,935
Warrants to purchase common stock
Anti-dilutive Securities
Anti-dilutive as of end of each period	55,044	54,875

Liquidity and Management's Plans (Detail) - USD ($)			2 Months Ended	12 Months Ended
Liquidity and Management's Plans (Detail) - USD ($)	Jan. 23, 2017	Jul. 08, 2015	Mar. 06, 2017	Dec. 31, 2016	Dec. 31, 2014	Dec. 30, 2016	Nov. 01, 2016	May 02, 2016	Jan. 11, 2016	Dec. 31, 2015	Nov. 09, 2015	Nov. 04, 2015	Sep. 15, 2015	Dec. 31, 2013
Liquidity and Managements Plans [Line Items]
Cash and cash equivalents				$ 3,310,787	$ 11,619,167					$ 7,927,240				$ 23,297,479
Gross proceeds before deducting estimate offering expenses		$ 16,000,000
Offering costs		1,400,000		28,000
Proceeds from warrants exercised				5,000	$ 2,242,265
Subsequent Event
Liquidity and Managements Plans [Line Items]
Gross proceeds before deducting estimate offering expenses	$ 19,000,000
Offering costs	$ 2,500,000
Common stock warrants			559,256
Proceeds from warrants exercised			$ 3,100,000
Senior Amortizing Convertible Note
Liquidity and Managements Plans [Line Items]
Senior amortizing convertible notes issued				$ 18,700,000								$ 25,000,000
Senior Amortizing Convertible Note \| First closing
Liquidity and Managements Plans [Line Items]
Senior amortizing convertible notes issued											$ 1,500,000		$ 1,500,000
Common stock warrants											1,679
Senior Amortizing Convertible Note \| Second closing
Liquidity and Managements Plans [Line Items]
Senior amortizing convertible notes issued									$ 11,000,000
Common stock warrants									12,312
Senior Amortizing Convertible Note \| Third closing
Liquidity and Managements Plans [Line Items]
Senior amortizing convertible notes issued						$ 6,250,000	$ 6,250,000	$ 6,250,000
Common stock warrants								6,995
Series A Warrants
Liquidity and Managements Plans [Line Items]
Gross proceeds before deducting estimate offering expenses		16,000,000
Offering costs		$ 1,400,000

Fair Value Measurements (Detail) - USD ($)			12 Months Ended
Fair Value Measurements (Detail) - USD ($)	May 02, 2016	Jan. 11, 2016	Dec. 31, 2016	Dec. 31, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value outstanding notes			$ 1,300,000
First closing
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value outstanding notes				$ 1,300,000
Second closing
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value outstanding notes		$ 2,400,000
Third closing
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value outstanding notes	$ 6,000,000
Notes Issued November 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates				1.11%
Expected life				1 year 10 months 10 days
Expected volatility				57.50%
Fair value per share of common stock				$ 1.95
Notes Issued January 11, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates		1.01%
Expected life		1 year 9 months 29 days
Expected volatility		60.00%
Fair value per share of common stock		$ 1.33
Notes Issued May 2, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates	0.69%
Expected life	1 year 6 months 7 days
Expected volatility	65.00%
Fair value per share of common stock	$ 0.80
Series A Warrants Issued July 8, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates			1.20%	0.91%
Expected life			24 months	42 months
Expected volatility			122.03%	89.89%
Fair value			$ 36,000	$ 2,759,583
Warrants Issued November 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates			1.47%	1.75%
Expected life			46 months	60 months
Expected volatility			102.29%	84.85%
Fair value			$ 449	$ 118,234
Warrants Issued January 11, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates		1.58%	1.93%
Expected life		60 months	48 months
Expected volatility		85.90%	108.57%
Fair value		$ 515,157	$ 1,633
Warrants Issued May 2, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rates	1.32%		1.93%
Expected life	60 months		52 months
Expected volatility	89.28%		106.37%
Fair value	$ 150,195		$ 1,037

Fair Value Measurements Senior Amortizing Convertible Notes and Common Stock Warrants (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior amortizing convertible notes (net of discounts of $149,340)		$ 1,267,182
Total		4,144,999
Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of warrants	$ 39,119	2,877,817
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		2,877,817
Level 2 \| Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of warrants	$ 39,119	2,877,817
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior amortizing convertible notes (net of discounts of $149,340)		1,267,182
Total		$ 1,267,182

Fair Value Measurements Senior Amortizing Convertible Notes and Common Stock Warrants (Parenthetical) (Detail)	Dec. 31, 2015 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Senior amortizing convertible notes, discounts	$ 149,340

Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Senior amortizing convertible notes principal and interest converted into shares of common stock	$ 20,300,000	$ 100,000
Gains (losses) resulting from conversion of senior amortizing convertible notes	$ 0

Inventory (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Long-term inventory	$ 676,000	$ 519,000

Inventory - Additional Information (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 335,606	$ 576,898
Work-in-process	1,437,957	1,066,345
Finished goods	16,015	43,081
Inventory	$ 1,789,578	$ 1,686,324

Property and Equipment (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Furniture and equipment	$ 2,302,878	$ 2,299,290
Computer hardware and software	596,292	585,880
Leasehold improvements	62,651	62,651
Property and Equipment, Gross	2,961,821	2,947,821
Less accumulated depreciation and amortization	(2,761,101)	(2,621,525)
Property and equipment, net	$ 200,720	$ 326,296

Accrued Expenses (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Professional service related expenses	$ 1,858,912	$ 1,912,775
Payroll related expenses	507,327	1,270,208
Other expenses	385,176	412,432
Accrued expenses	$ 2,751,415	$ 3,595,415

Senior Amortizing Convertible Notes (Detail) - USD ($)						1 Months Ended						3 Months Ended				12 Months Ended
Senior Amortizing Convertible Notes (Detail) - USD ($)	Dec. 30, 2016	May 02, 2016	Jan. 11, 2016	Nov. 09, 2015	Nov. 04, 2015	Dec. 31, 2016	Nov. 30, 2016	Oct. 31, 2016	Sep. 30, 2016	Aug. 31, 2016	Jul. 31, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Mar. 06, 2017	Jan. 20, 2017	Nov. 01, 2016	Jan. 29, 2016	Sep. 15, 2015
Debt Instrument [Line Items]
Convertible notes, interest rate				7.00%
Convertible notes, per share price		$ 325.50	$ 325.50	$ 304.50																	$ 76.30
Exercise price																					$ 76.30
Convertible notes, maturity period				24 months
Fair value of outstanding notes						$ 1,300,000						$ 1,300,000				$ 1,300,000
Warrants issued, exercisable time period				60 months
Stock Issued (in shares)				27,982
Subsequent Event
Debt Instrument [Line Items]
Exercise price																			$ 2.18
Common stock warrants																		559,256
First closing
Debt Instrument [Line Items]
Shares issued upon on conversion of notes (in shares)													94,948	12,306	5,112		1,003
Fair value of outstanding notes																	$ 1,300,000
Second closing
Debt Instrument [Line Items]
Shares issued upon on conversion of notes (in shares)												1,272,987	612,532	58,658	14,974
Fair value of outstanding notes			$ 2,400,000
Third closing
Debt Instrument [Line Items]
Shares issued upon on conversion of notes (in shares)						81,872	64,828	48,192	34,523	34,684	13,168	1,265,846	254,247	16,600
Fair value of outstanding notes		$ 6,000,000
Minimum
Debt Instrument [Line Items]
Common stock ownership percentage required to exercise warrants				4.99%
Period available for the percentage to be effective				61 days
Maximum
Debt Instrument [Line Items]
Common stock ownership percentage required to exercise warrants				9.99%
Senior Amortizing Convertible Note
Debt Instrument [Line Items]
Convertible notes, interest rate					7.00%
Senior convertible notes, maturity year					2017
Convertible notes, per share price					$ 304.50
Senior amortizing convertible notes to be issued					$ 25,000,000	$ 18,700,000						$ 18,700,000				$ 18,700,000
Exercise price					$ 325.50
Proceeds from issuance of debt instrument including warrants					$ 12,500,000
Shares issued upon on conversion of notes (in shares)																2,632,000
Senior Amortizing Convertible Note \| First closing
Debt Instrument [Line Items]
Senior amortizing convertible notes to be issued				$ 1,500,000																		$ 1,500,000
Common stock warrants				1,679
Senior Amortizing Convertible Note \| Second closing
Debt Instrument [Line Items]
Senior amortizing convertible notes to be issued			$ 11,000,000
Common stock warrants			12,312
Fair value of warrants			$ 515,000
Senior Amortizing Convertible Note \| Third closing
Debt Instrument [Line Items]
Senior amortizing convertible notes to be issued	$ 6,250,000	$ 6,250,000																		$ 6,250,000
Proceeds from issuance of debt instrument including warrants	$ 6,250,000
Common stock warrants		6,995
Fair value of warrants		$ 150,195

Senior Amortizing Convertible Notes - Additional Information (Detail) - USD ($)	1 Months Ended						3 Months Ended				12 Months Ended
	Dec. 31, 2016	Nov. 30, 2016	Oct. 31, 2016	Sep. 30, 2016	Aug. 31, 2016	Jul. 31, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Short-term Debt [Line Items]
Total											$ 20,318,024	$ 109,504
First closing
Short-term Debt [Line Items]
Principal								$ 1,500,000	$ 504,974	$ 318,696		83,478
Interest								210,292	115,680	77,296		26,026
Total								$ 1,710,292	$ 620,654	$ 395,992		$ 109,504
Common Shares								94,948	12,306	5,112		1,003
First closing \| Installment payments December 31, 2015
Short-term Debt [Line Items]
Principal												$ 65,217
Interest												23,651
Total												$ 88,868
Common Shares												814
First closing \| Installment payments February 29, 2016
Short-term Debt [Line Items]
Principal										$ 65,217
Interest										23,681
Total										$ 88,898
Common Shares										1,314
First closing \| Installment payments March 31, 2016
Short-term Debt [Line Items]
Principal										$ 65,217
Interest										14,827
Total										$ 80,044
Common Shares										1,271
First closing \| Installment payments April 30, 2016
Short-term Debt [Line Items]
Principal									$ 65,217
Interest									13,853
Total									$ 79,070
Common Shares									1,454
First closing \| Installment payments May 31, 2016
Short-term Debt [Line Items]
Principal									$ 65,217
Interest									13,082
Total									$ 78,299
Common Shares									2,121
First closing \| Installment payments June 30 , 2016
Short-term Debt [Line Items]
Principal									$ 54,217
Interest									11,275
Total									$ 65,492
Common Shares									3,590
First closing \| Installment payments July 31, 2016
Short-term Debt [Line Items]
Principal								$ 65,217
Interest								10,148
Total								$ 75,365
Common Shares								5,521
First closing \| Installment payments August 31, 2016
Short-term Debt [Line Items]
Principal								$ 46,957
Interest								5,830
Total								$ 52,787
Common Shares								4,593
Second closing
Short-term Debt [Line Items]
Principal							$ 11,000,000	$ 8,636,386	$ 2,518,087	$ 1,391,762
Interest							1,410,249	1,223,934	595,273	273,350
Total							$ 12,410,249	$ 9,860,320	$ 3,113,360	$ 1,665,112
Common Shares							1,272,987	612,532	58,658	14,974
Second closing \| Installment payments May 31, 2016
Short-term Debt [Line Items]
Principal									$ 291,428
Interest									86,518
Total									$ 377,946
Common Shares									10,238
Second closing \| Installment payments June 30 , 2016
Short-term Debt [Line Items]
Principal									$ 404,762
Interest									82,913
Total									$ 487,675
Common Shares									22,842
Second closing \| Installment payments July 31, 2016
Short-term Debt [Line Items]
Principal							$ 340,000	$ 213,429
Interest							24,738	47,457
Total							$ 364,738	$ 260,886
Common Shares							70,665	19,113
Second closing \| Installment payments August 31, 2016
Short-term Debt [Line Items]
Principal							$ 291,429	$ 631,429
Interest							27,528	116,511
Total							$ 318,957	$ 747,940
Common Shares							81,952	64,810
Second closing \| Installment payments March 2, 2016
Short-term Debt [Line Items]
Principal										$ 404,762
Interest										149,300
Total										554,062
Second closing \| Installment payments April 29, 2016
Short-term Debt [Line Items]
Principal									$ 404,762
Interest									149,497
Total									$ 554,259
Common Shares									10,190
Second closing \| Installment payments September 30, 2016
Short-term Debt [Line Items]
Principal							$ 156,867	$ 404,762
Interest							11,425	45,846
Total							$ 168,292	$ 450,608
Common Shares							57,453	51,698
Third closing
Short-term Debt [Line Items]
Principal	$ 221,053	$ 221,053	$ 221,053	$ 263,158	$ 336,842	$ 147,368	$ 6,250,000	$ 2,917,329	$ 212,158
Interest	14,526	31,259	35,004	41,822	62,059	32,374	659,261	408,113	90,659
Total	$ 235,579	$ 252,312	$ 256,057	$ 304,980	$ 398,901	$ 179,742	$ 6,909,261	$ 3,325,442	$ 302,817
Common Shares	81,872	64,828	48,192	34,523	34,684	13,168	1,265,846	254,247	16,600
Third closing \| Cash Payment July 31, 2016 Installment
Short-term Debt [Line Items]
Principal						$ 42,105
Interest						6,107
Total						$ 48,212
Holder Conversions \| First closing
Short-term Debt [Line Items]
Principal								$ 882,852	$ 1,627	104,784		$ 18,261
Interest								78,634	174	12,762		2,375
Total								$ 961,486	$ 1,801	$ 117,546		$ 20,636
Common Shares								72,528	29	1,524		189
Holder Conversions \| Second closing
Short-term Debt [Line Items]
Principal							$ 1,575,318	$ 4,868,679	$ 25,373	$ 987,000
Interest							122,624	418,847	2,995	124,050
Total							$ 1,697,942	$ 5,287,526	$ 28,368	$ 1,111,050
Common Shares							450,385	418,253	414	14,974
Holder Conversions \| Third closing
Short-term Debt [Line Items]
Principal	$ 2,669,512			$ 1,915,698
Interest	170,359			175,092
Total	$ 2,839,871			$ 2,090,790
Common Shares	816,707			155,272

Preferred Stock (Detail) - $ / shares	Jan. 24, 2017	Jan. 23, 2017	Dec. 31, 2016	Dec. 31, 2015
Preferred Stock [Line Items]
Preferred stock, authorized			5,000,000
Preferred stock, par value			$ 0.01
Preferred stock, issued			0	0
Preferred stock, outstanding			0	0
Subsequent Event
Preferred Stock [Line Items]
Preferred stock, outstanding		12,531
Subsequent Event \| Preferred Stock
Preferred Stock [Line Items]
Preferred stock, outstanding		12,531
Shares issued upon conversion (in shares)	2,359,894

Stock Sales (Detail) - USD ($)			12 Months Ended
Stock Sales (Detail) - USD ($)	Jul. 08, 2015	Jun. 13, 2014	Dec. 31, 2016	Jan. 20, 2017	Jan. 29, 2016	Nov. 09, 2015
Class of Stock [Line Items]
Public offering selling units	30,476
Shares issued, price per unit	$ 525.00
Gross proceeds before deducting estimate offering expenses	$ 16,000,000
Offering costs	$ 1,400,000		$ 28,000
Exercise price					$ 76.30
Beneficial ownership percentage	9.99%
Warrants to purchase common stock
Class of Stock [Line Items]
Offering costs	$ 532,000
Series C Warrants
Class of Stock [Line Items]
Exercise price	$ 525.00
Warrant issued	0
Series A Warrants
Class of Stock [Line Items]
Gross proceeds before deducting estimate offering expenses	$ 16,000,000
Offering costs	$ 1,400,000
Exercise price	$ 630.00		$ 2.80		$ 67.90	$ 168.00
Warrants exercisable period	42 months
Forecast \| Series A Warrants
Class of Stock [Line Items]
Exercise price				$ 2.18
Cowen and Company LLC
Class of Stock [Line Items]
Gross proceeds before deducting estimate offering expenses			$ 7,600,000
Commission or discount percentage on issue of shares		3.00%
Number of shares sold			5,256
Minimum
Class of Stock [Line Items]
Beneficial ownership percentage	4.99%
Weighted Average \| Cowen and Company LLC
Class of Stock [Line Items]
Sale of stock, price per share			$ 1,442.00
Maximum \| Cowen and Company LLC
Class of Stock [Line Items]
Gross proceeds before deducting estimate offering expenses		$ 25,000,000	$ 17,400,000

Income Taxes (Detail)	12 Months Ended
Income Taxes (Detail)	Dec. 31, 2016 USD ($)	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	34.00%	34.00%	34.00%
Percentage of change in ownership	50
U.S. federal net operating loss carryforwards amount	$ 161,400,000
Federal net operating loss carryforward Expiration	48,000,000
Excess tax benefit not yet recorded	$ 221,000

Income Taxes - Tax Rate Reconciliation (Detail)	12 Months Ended
Income Taxes - Tax Rate Reconciliation (Detail)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Computed 'expected' tax benefit	34.00%	34.00%	34.00%
Other permanent adjustments	3.10%	1.60%	(2.30%)
Research and development credit	0.60%	0.90%	0.30%
Federal valuation allowance	(37.70%)	(36.50%)	(32.00%)

Income Taxes - Deferred Tax Assets (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets (liabilities):
Start-up costs	$ 6,662,000	$ 8,886,000
Capitalized research and development costs	23,012,000	29,781,000
Reserves and accruals	8,933,000	8,121,000
Property and equipment	83,000	107,000
Research and development credit	2,198,000	1,972,000
Net operating loss carryforwards	41,657,000	25,695,000
Total gross deferred tax assets	82,545,000	74,562,000
Valuation allowance	$ (82,545,000)	$ (74,562,000)

Stock Options (Detail) - USD ($)		12 Months Ended
Stock Options (Detail) - USD ($)	Jun. 27, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 08, 2017	Feb. 07, 2017
Schedule Of Stock Options [Line Items]
Stock incentive plan, shares authorized		40,000,000	18,857
Options granted to participants		10.00%
Option to purchase	6,424
Award granted, shares	1,083	2,174	3,238	1,197
Option exercise price (dollars per share)	$ 23.28
Award granted, exercise price per share		$ 45.35	$ 1,104.00	$ 1,712.00
Weighted average estimated fair value of stock options granted		$ 60.00	$ 426.30	$ 1,486.00
Total unrecognized compensation costs related to non-vested stock options		$ 2,800,000
Total unrecognized compensation costs related to non-vested stock options, weighted-average period of recognition		2 years 2 months 12 days
Aggregate intrinsic value of stock options		$ 0	$ 0	$ 0
Subsequent Event
Schedule Of Stock Options [Line Items]
Stock incentive plan, shares authorized					3,000,000	40,000,000
Incentive Stock Options
Schedule Of Stock Options [Line Items]
Options granted to participants		10.00%
Employees \| Employee Awards
Schedule Of Stock Options [Line Items]
Award vesting period		4 years
Nonemployees
Schedule Of Stock Options [Line Items]
Stock-based compensation		$ 3,535	$ (34,712)	$ 181,323
Minimum
Schedule Of Stock Options [Line Items]
Options granted to participants owning more than 10% of outstanding voting stock, exercise price percentage		110.00%
Minimum \| Incentive Stock Options
Schedule Of Stock Options [Line Items]
Option expiration period		5 years
Maximum
Schedule Of Stock Options [Line Items]
Option expiration period		10 years

Stock Options - Summary of Stock Option Activity (Detail) - USD ($)		12 Months Ended
	Jun. 27, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available For Grant, Beginning Balance		4,237	6,740	519
Shares Available For Grant, Shares reserved		2,976,486		7,143
Shares Available For Grant, Options granted		(2,174)	(3,238)	(1,197)
Shares Available For Grant, Options cancelled		9,694	735	275
Shares Available For Grant, Ending Balance		2,988,243	4,237	6,740
Outstanding Options, Number of Shares, Beginning Balance		14,554	12,051	11,129
Outstanding Options, Number of Shares, Options granted	1,083	2,174	3,238	1,197
Outstanding Options, Number of Shares, Options cancelled		(9,694)	(735)	(275)
Outstanding Options, Number of Shares, Ending Balance		7,034	14,554	12,051
Outstanding Options, Weighted-Average Exercise Price, Beginning Balance		$ 2,298.00	$ 2,597.00	$ 2,660.00
Outstanding Options, Weighted-Average Exercise Price, Options granted		45.35	1,104.00	1,712.00
Outstanding Options, Weighted-Average Exercise Price, Options cancelled		2,134.47	1,942.00	2,528.00
Outstanding Options, Weighted-Average Exercise Price, Ending Balance		$ 1,824.87	$ 2,298.00	$ 2,597.00
Aggregate Intrinsic Value				$ 519,546
Vesting One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage		25.00%
Vesting Period		1 year
Vesting Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage		75.00%
Vesting Period		36 months
Monthly vesting percentage		2.0833%
Stock Incentive Plan 2003
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available For Grant, Shares reserved		5,426	7,380
Shares Available For Grant, Options granted		(5,426)	(7,380)
Outstanding Options, Number of Shares, Beginning Balance		7,380
Outstanding Options, Number of Shares, Options granted		5,426	7,380
Outstanding Options, Number of Shares, Ending Balance		12,806	7,380
Outstanding Options, Weighted-Average Exercise Price, Beginning Balance		$ 262.50
Outstanding Options, Weighted-Average Exercise Price, Options granted		94.05	$ 262.50
Outstanding Options, Weighted-Average Exercise Price, Ending Balance		$ 191.12	$ 262.50

Stock Options - Outstanding Vested and Currently Exercisable by Exercise Price (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares outstanding	19,840
Aggregate Intrinsic Value		$ 519,546
Number of Options	8,662
Weighted-Average Exercise Price	$ 1,538.71
$0.01 to $25.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price, lower limit	0.01
Exercise price, upper limit	$ 25.00
Number of shares outstanding	829
Weighted-Average Remaining Contractual Life (Years)	9 years 6 months
Number of Options	498
Weighted-Average Exercise Price	$ 23.12
$25.01 to $175.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price, lower limit	25.01
Exercise price, upper limit	$ 175.00
Number of shares outstanding	6,416
Weighted-Average Remaining Contractual Life (Years)	9 years 1 month 6 days
Number of Options	846
Weighted-Average Exercise Price	$ 72.56
$175.01 to $350.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price, lower limit	175.01
Exercise price, upper limit	$ 350.00
Number of shares outstanding	7,644
Weighted-Average Remaining Contractual Life (Years)	8 years 9 months 18 days
Number of Options	2,407
Weighted-Average Exercise Price	$ 260.78
$350.01 to $1475.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price, lower limit	350.01
Exercise price, upper limit	$ 1,475.00
Number of shares outstanding	2,073
Weighted-Average Remaining Contractual Life (Years)	7 years 2 months 12 days
Number of Options	2,041
Weighted-Average Exercise Price	$ 1,321.12
> $1475.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price, lower limit	$ 1,475.00
Number of shares outstanding	2,878
Weighted-Average Remaining Contractual Life (Years)	5 years 1 month 6 days
Number of Options	2,870
Weighted-Average Exercise Price	$ 3,460.40

Stock Options - Stock-Based Compensation for Non Employees (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividends	0.00%	0.00%
Nonemployees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rates, minimum	0.02%	0.08%
Risk-free interest rates, maximum	2.10%	2.63%
Expected Volatility, minimum	37.36%	56.54%
Expected Volatility, maximum	132.01%	139.65%
Nonemployees \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	29 days	6 months
Nonemployees \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	8 years 6 months 4 days	9 years 6 months 4 days

Stock Options - Estimated Grant-Date Fair Values of Employee Stock Options (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividends		0.00%	0.00%
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rates, minimum	0.87%	1.49%	1.73%
Risk-free interest rates, maximum	1.64%	1.80%	1.96%
Expected dividends	0.00%	0.00%	0.00%
Expected volatility, minimum	88.43%	83.36%	118.64%
Expected volatility, maximum	114.38%	111.77%	120.70%
Minimum \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	4 years	5 years 6 months	6 years
Maximum \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life	6 years 3 months	6 years 3 months	6 years 3 months

Warrants (Detail) - Common Stock - $ / shares	12 Months Ended
Warrants (Detail) - Common Stock - $ / shares	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Warrant or Right [Line Items]
Beginning Balance	54,875	23,044	24,331
Granted	19,308	32,155
Exercised	(1,428)		(1,265)
Cancelled	(17,706)	(324)	(22)
Ending Balance	55,049	54,875	23,044
Beginning Balance	$ 1,929.20	$ 1,929.20	$ 1,964.90
Granted	325.50	116.20
Exercised	3.50		1,772.40
Cancelled	2,257.50	(2,299.50)	50,988.00
Ending Balance	$ 238.90	$ 1,929.20	$ 1,929.20

Warrants - Additional Information (Detail)	12 Months Ended
Warrants - Additional Information (Detail)	Dec. 31, 2016	Dec. 31, 2015
Warrants to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant outstanding, weighted-average remaining contractual life	2 years 9 months 4 days	2 years 2 months 5 days

Related Party Transactions (Detail) - USD ($)			12 Months Ended
Related Party Transactions (Detail) - USD ($)	Nov. 09, 2015	Aug. 10, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Stock Issued (in shares)	27,982
Selling, general and administrative expenses			$ 17,981,525	$ 19,892,424	$ 14,561,656
Consulting Agreement - Anthony Jansz
Related Party Transaction [Line Items]
Consulting agreement beginning date			Jun. 01, 2011
Consulting agreement termination date			Apr. 30, 2015
Award granted, shares			16,663
Award granted, price per share			$ 29.78
Stock-based compensation				600	40,000
Options granted not vest			471
Payment for consulting services				75,000	196,000
Consulting Services
Related Party Transaction [Line Items]
Selling, general and administrative expenses					$ 253,000
Consulting Agreement - Jon Tremmel
Related Party Transaction [Line Items]
Award granted, shares		16,666
Award granted, price per share		$ 3.45
Stock-based compensation			$ 3,000	13,000
Payment for consulting services			$ 0	$ 50,000
Consulting agreement term		1 year
Common Stock
Related Party Transaction [Line Items]
Stock Issued (in shares)				4,604	4,468

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions			12 Months Ended
	Nov. 09, 2015	Jul. 08, 2015	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Stock Issued (in shares)	27,982
Proceeds, before expenses, to the Company		$ 16.0
Common Stock
Related Party Transaction [Line Items]
Stock Issued (in shares)			4,604	4,468

Commitments and Contingencies (Detail)			12 Months Ended
Commitments and Contingencies (Detail)	Feb. 28, 2017 shareholder defendant shares	Aug. 25, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Operating lease agreement expiration date		Sep. 30, 2018	Sep. 30, 2015
Operating lease agreement term		3 years
Total rent expense			$ 229,000	$ 262,000	$ 271,000
Number of months that require patients to be followed out in clinical trials			60 months
Subsequent Event \| Du Litigation
Loss Contingencies [Line Items]
Number of shareholders \| shareholder	1
Number of Senior Management members \| defendant	4
Number of Shares \| shares	1,093,450
Minimum
Loss Contingencies [Line Items]
Operating lease, monthly base rent		$ 18,925
Maximum
Loss Contingencies [Line Items]
Operating lease, monthly base rent		$ 20,345

Commitments and Contingencies - Additional Information (Detail)	Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2017	$ 237,749
2018	183,103
Operating Leases, Future Minimum Payments Due, Total	$ 420,852

Quarterly Information (Detail) - USD ($)	3 Months Ended								12 Months Ended
Quarterly Information (Detail) - USD ($)	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Data [Abstract]
Revenue	$ 142	$ 297	$ 276	$ 72	$ 149	$ 64	$ 79		$ 786,660	$ 292,000
Net loss	$ (4,434,000)	$ (6,522,000)	$ (4,995,000)	$ (7,409,000)	$ (6,770)	$ (4,151)	$ (7,404)	$ (7,174)	$ (23,360,844)	$ (25,498,747)	$ (26,128,720)
Basic and diluted net loss per share	$ (2.65)	$ (11.77)	$ (33.96)	$ (66.14)	$ (66.70)	$ (41.92)	$ (104.48)	$ (103.56)	$ (37.53)	$ (298.97)	$ (404.25)
Reduction in net loss	$ 2,400,000
Decrease in Operating Expenses					$ 3,500,000
Increase in interest expense	600,000
Expenses from net changes in warrant liability and convertible note liability valuations	$ 500,000

Subsequent Events (Detail) - USD ($)					2 Months Ended	12 Months Ended
Subsequent Events (Detail) - USD ($)	Jan. 24, 2017	Jan. 23, 2017	Nov. 09, 2015	Jul. 08, 2015	Mar. 06, 2017	Dec. 31, 2016	Dec. 31, 2014	Jan. 20, 2017	Jan. 29, 2016	Dec. 31, 2015
Gross proceeds before deducting estimate offering expenses				$ 16,000,000
Offering costs				$ 1,400,000		$ 28,000
Exercise price									$ 76.30
Beneficial ownership percentage				9.99%
Common stock (in shares)						2,736,621				102,415
Preferred stock ( in shares)						0				0
Common stock shares issued (in shares)			27,982
Proceeds from warrants exercised						$ 5,000	$ 2,242,265
Subsequent Event
Gross proceeds before deducting estimate offering expenses		$ 19,000,000
Offering costs		$ 2,500,000
Exercise price								$ 2.18
Common stock warrants					559,256
Beneficial ownership percentage		4.99%
Liquidation or other preference		$ 0
Common stock (in shares)		1,218,107
Preferred stock ( in shares)		12,531
Proceeds from warrants exercised					$ 3,100,000
Subsequent Event \| Over-allotment option
Common stock shares issued (in shares)		466,695
Subsequent Event \| Preferred Stock
Shares issued upon conversion (in shares)	2,359,894
Preferred stock ( in shares)		12,531
Subsequent Event \| Class A Units
Offer price		$ 5.31
Warrant term		5 years
Exercise price		$ 5.84
Shares issued upon conversion (in shares)		188
Subsequent Event \| Class B Units
Offer price		$ 1,000
Shares issued upon conversion (in shares)	2,359,894	2,359,894
Common stock warrants		3,577,994
Subsequent Event \| Warrants 2017
Common stock warrants		188
Subsequent Event \| Warrants 2017 \| Over-allotment option
Common stock shares issued (in shares)		466,695