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Expenses recognized from issuance of warrants.

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Warrants issued to purchase common stock.

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The number of exercisable share warrants that may be converted as of the balance sheet date.

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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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Stock options expiration term.

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Warrants exercisable price per share.

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Per share amount of warrant.

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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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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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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 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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Stock-Based Compensation (Details Textual) (USD $)	12 Months Ended			1 Months Ended			12 Months Ended		0 Months Ended
Stock-Based Compensation (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 25, 2012	Mar. 15, 2012	Dec. 20, 2011	Dec. 31, 2001	Dec. 31, 2007	Oct. 10, 2014	Apr. 03, 2009	Nov. 02, 2010	Mar. 20, 2007
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	2,382,500	222,500	2,075,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	$ 4,700,000
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options	4,000	232,000	2,100,000
Sale of Stock, Price Per Share										$ 5us-gaap_SaleOfStockPricePerShare
Proceeds from Issuance of Common Stock	20,668,000	13,224,000	10,800,000
Change in fair value of warrant liabilities	(620,000)us-gaap_FairValueAdjustmentOfWarrants	0us-gaap_FairValueAdjustmentOfWarrants	0us-gaap_FairValueAdjustmentOfWarrants
Warrant liabilities	6,756,000syn_WarrantLiabilities	0syn_WarrantLiabilities
Class of Warrant or Right, Outstanding	316,522
Stock Options Expiration Term	June 2018
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
Share-based Compensation Arrangement by Share-based Payment Award, Warrants, Exercisable Number					250,000	100,000
Share-based Compensation Arrangement by Share-based Payment Award, Warrants, Vested and Expected to Vest Outstanding, Number					50,000
Warrants Exercisable Price Per Share					$ 2.20
Issuance of Warrants Expenses Recognized	0	0	63,000
Fair Value Warrants						200,000
Epitope [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	50,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	50,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 0.001
General and Administrative Expenses and Research and Development Expense [Member] \| Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense			271,000
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	2,382,500	222,500	2,075,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value	5,000,000	350,000	4,500,000
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	2,100,000	1,300,000	1,400,000
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	380,000	324,000	216,000
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	682,449
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	428,657										3,000,000	2,500,000
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	4,870,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	682,449
2010 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	6,000,000
2010 Stock Plan [Member] \| Minimum [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	3,000,000
Stock Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of Warrants to Purchase of Common Stock									0.5
Investment Warrants Expiration Date									Oct. 10, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Warrants, Exercisable Number									7,029,808
Share-based Compensation Arrangement by Share-based Payment Award, Warrants, Vested and Expected to Vest Outstanding, Number									1.75
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	620,000								7,400,000
Warrant liabilities	$ 6,800,000