Convertible Preferred Stock And Stockholders' Equity (Narrative) (Details)			1 Months Ended			12 Months Ended
	Mar. 05, 2018 $ / shares shares	Sep. 29, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($)	Jun. 30, 2014 shares	May 31, 2014 USD ($)	Dec. 31, 2017 USD ($) $ / shares item shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2009 USD ($)	Sep. 26, 2016 $ / shares
Shareholders' Equity and Share-based Payments [Line Items]
Votes per share | item						1
Dividends declared						$ 0
Dividends paid						$ 0
Proceeds from preferred stock and warrants issued, gross		$ 24,000,000
Preferred stock, shares issued | shares		24,000
Preferred stock, par value | $ / shares						$ 0.001	$ 0.001
Preferred Stock, Liquidation Preference, Value						$ 1,000
Common stock issuable from warrants | shares		36,923,078
Proceeds from preferred stocks and warrants, net		$ 23,000,000
Payments of debt							$ 13,020,780
Preferred stock dividend rate						6.00%
Preferred stock, conversion price | $ / shares						$ 0.65
Preferred stock redemption, triggering event, Percent of common stock sold threshold						50.00%
Preferred stock, Accretion of dicount						$ 6,100,000	6,145,402
Exercise price of warrants | $ / shares		$ 0.70							$ 0.70
Proceeds from issuance of stock, net of issuance costs						41,054	$ 23,001,528
Total compensation cost not yet recognized						$ 500,000
Weighted average amortization period of total compensation cost not yet recognized						4 years
Subsequent Event [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Exercise price of warrants | $ / shares	$ 0.28
Number of warrants exercised | shares	35,791,927
Convertible Preferred Stock [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Shares converted | shares							100
Common Stock [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Shares issued in conversion | shares							155,439
2009 Employee Stock Purchase Plan [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Exercise price as percentage of fair value								95.00%
Increase in number of shares authorized for issuance under the Plan | shares				250,000
Eligible employees new purchase period						3 months
Maximum percentage of compensation eligible employees can use to purchase common stock								15.00%
Compensation amount eligible employees can use to purchase common stock, maximum								$ 25,000
Remaining shares available for issuance | shares						125,618
Sales Agreement [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Aggregate gross sales price					$ 18,000,000
Commission percentage of gross proceeds					3.00%
Stock Options And Stock Appreciation Rights [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options expiration term						10 years
Options and stock appreciation rights outstanding | shares						413,301	671,887
Options and stock appreciation rights vested and exercisable | shares						339,002
Weighted average remaining contractual life						6 years 26 days
Options vested with exercise price below share price | shares						0
Options and stock appreciation rights exercised | shares						0	0
Options and stock appreciation rights weighted average exercise price | $ / shares						$ 10.56
Options and stock appreciation rights weighted average remaining term						5 years 9 months 18 days
Options and stock appreciation rights intrinsic value						$ 1,800
Proceeds from options and stock appreciation rights exercised						$ 0	$ 0
Weighted average grant date fair value of options and stock appreciation rights granted | $ / shares						$ 0.62
Share price | $ / shares						$ 0.80
Stock Options And Stock Appreciation Rights [Member] | Tranche One [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting percentage						25.00%
Stock Options And Stock Appreciation Rights [Member] | Tranche Two [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting percentage						2.0833%
Options vesting period						3 years
Stock Options And Stock Appreciation Rights [Member] | Director [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options expiration term						10 years
Stock Options And Stock Appreciation Rights [Member] | Director [Member] | Tranche One [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting period						2 years
Stock Options And Stock Appreciation Rights [Member] | Minimum [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Exercise price as percentage of fair value						100.00%
Stock Options And Stock Appreciation Rights [Member] | Minimum [Member] | Director [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Exercise price as percentage of fair value						100.00%
Warrants [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Exercise price of warrants | $ / shares						$ 0.82
Stock Appreciation Rights [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options expiration term						10 years
Stock Appreciation Rights [Member] | Tranche One [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting percentage						25.00%
Stock Appreciation Rights [Member] | Tranche Two [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting percentage						2.0833%
Options vesting period						3 years
Restricted Stock [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting period						3 years
Restricted shares outstanding | shares						0
Restricted Stock Units [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Options vesting period						4 years
Intrinsic value of restricted awards outstanding						$ 500,000
Intrinsic value of restricted awards vested						$ 400,000
Restricted shares outstanding | shares						680,363	1,167,099
Share price | $ / shares						$ 0.80
Healthcare Royalty Partners Debt [Member]
Shareholders' Equity and Share-based Payments [Line Items]
Payments of debt			$ 13,000,000			$ 13,000,000