Expiration date of warrants held.

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Warrants issued to purchase common stock.

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Fair value of stock (or other type of equity) granted during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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As of the balance sheet date, the number of warrants into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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No definition available.

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Stock options expiration term.

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It represents value of warrant liabilities.

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Per share amount of warrant.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Number of warrants or rights outstanding.

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- Definition

Aggregate number of common shares reserved for future issuance.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

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The cash inflow from the additional capital contribution to the entity.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Stock-Based Compensation (Details Textual) - USD ($)		1 Months Ended		12 Months Ended
Stock-Based Compensation (Details Textual) - USD ($)	Oct. 10, 2014	Oct. 25, 2012	Mar. 20, 2007	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2001	May. 15, 2015	Oct. 22, 2013	Nov. 02, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options				$ 8,300,000
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options				41,000	$ 4,000	$ 232,000
Proceeds from Issuance of Common Stock				46,000,000	20,668,000	13,224,000
Change in fair value of warrant liabilities				3,811,000	(620,000)	0
Warrant liabilities				$ 10,567,000	$ 6,756,000	$ 0
Class of Warrant or Right, Outstanding				311,834
Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of Warrants to Purchase of Common Stock		635,855
Warrants Exercise Price Per Share		$ 1.60
Investment Warrants Expiration Date		Oct. 25, 2017
Epitope [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options Expiration Term				Jun 30, 2018
Employees And Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				3,781,666	2,382,500	222,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value				$ 8,000,000	$ 5,000,000	$ 350,000
Employee [Member] \| General and Administrative Expenses and Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense				2,300,000	2,100,000	1,300,000
Consultant [Member] \| General and Administrative Expenses and Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense				$ 888,000	380,000	$ 324,000
2001 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				671,607
2001 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							250,000
2007 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			2,500,000	428,657
2007 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			250,000
2010 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				7,841,666						3,000,000
2010 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance								8,000,000	6,000,000
2010 Stock Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance								6,000,000	3,000,000
Stock Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of Warrants to Purchase of Common Stock	0.5
Share-based Compensation Arrangement by Share-based Payment Award, Warrants, Vested and Expected to Vest Outstanding, Number	1.75
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	7,029,808
Sale of Stock, Number of Shares Issued in Transaction	14,059,616
Sale of Stock, Price Per Share	$ 1.47
Proceeds from Issuance of Common Stock	$ 19,100,000
Change in fair value of warrant liabilities	$ 7,400,000			$ 3,800,000	620,000
Warrant liabilities				$ 10,600,000	$ 6,800,000