Consolidated Statements of Stockholders’ Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total USD ($)	Series C-1 Redeemable Convertible Preferred Stock [Member] USD ($)	Series C-1 Convertible Preferred Stock [Member] USD ($)	Series C-2 Convertible Preferred Stock [Member] USD ($)	Series D-1 Convertible Preferred Stock [Member] USD ($)	Series F Convertible Preferred Stock [Member] USD ($)	Convertible Preferred Stock [Member] Series C-1 Convertible Preferred Stock [Member] USD ($)	Convertible Preferred Stock [Member] Series C-2 Convertible Preferred Stock [Member] USD ($)	Convertible Preferred Stock [Member] Series D-1 Convertible Preferred Stock [Member] USD ($)	Convertible Preferred Stock [Member] Series F Convertible Preferred Stock [Member] USD ($)	Common Stock [Member] USD ($)	Common Stock [Member] Series C-1 Convertible Preferred Stock [Member]	Common Stock [Member] Series D-1 Convertible Preferred Stock [Member]	Additional Paid-in Capital [Member] USD ($)	Additional Paid-in Capital [Member] Series C-1 Convertible Preferred Stock [Member] USD ($)	Additional Paid-in Capital [Member] Series D-1 Convertible Preferred Stock [Member] USD ($)	Accumulated Deficit [Member] USD ($)
Beginning Balance at Dec. 31, 2011	$ (15,558)	$ 5,133					$ 0	$ 0	$ 0	$ 0	$ 0			$ 424,071			$ (439,629)
Beginning Balance, shares at Dec. 31, 2011		5,000					0	0	0	0	17,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Preferred Stock dividends, shares		1,000
Issuance of Preferred Stock dividends	(780)	780												(780)
Series C-1 Preferred Stock dividends	(56)	(90)												(56)
Conversion of Preferred Stock into common stock, shares												127,000	67,000
Conversion of Preferred Stock into common stock		(31)	31		0				(16)		1				30	16
Exercised Series C-2/D-1 warrants for Series C-2/D-1 Preferred Stock, shares								1,000	5,000
Exercised Series C-2/D-1 warrants for Series C-2/D-1 Preferred Stock				500	0			500	4,631							(4,631)
Share-based compensation expense	8,604													8,604
Issuance of restricted stock awards, shares											74,000
Issuance of restricted stock awards	0
Removal of redemption and certain conversion features, shares		(6,000)					6,000
Removal of redemption and certain conversion features	18,210	(5,792)					5,792							12,418
Net loss	(7,737)																(7,737)
Ending Balance at Dec. 31, 2012	3,214	0					5,792	500	4,615		1			439,672			(447,366)
Ending Balance, shares at Dec. 31, 2012		0					6,000	1,000	5,000		285,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock, shares											4,119,058	165,652	201,914
Ending Balance at Sep. 30, 2013
Beginning Balance at Dec. 31, 2012	3,214						5,792	500	4,615	0	1			439,672			(447,366)
Beginning Balance, shares at Dec. 31, 2012							6,000	1,000	5,000	0	285,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Preferred Stock dividends, shares							1,000
Issuance of Preferred Stock dividends	0						744	57						(801)
Conversion of Preferred Stock into common stock, shares							(1,000)				367,000
Conversion of Preferred Stock into common stock	0						(77)		(47)					124
Redemption of Series D-1 Preferred Stock, shares									(5,000)
Redemption of Series D-1 Preferred Stock	0								(4,568)					4,568
Exchange of Series C-2 Preferred Stock for Series C-1 Preferred Stock, shares							1,000	(1,000)
Exchange of Series C-2 Preferred Stock for Series C-1 Preferred Stock	0						557	(557)
Issuance of stock, shares										3,000	1,929,000
Issuance of stock	6,750					3,250				3,250	2			6,748
Share-based compensation expense	12,373													12,373
Issuance of restricted stock awards, shares											1,823,000
Issuance of restricted stock awards	1										1
Net loss	(17,935)																(17,935)
Ending Balance at Dec. 31, 2013	$ 7,653	$ 0					$ 7,016	$ 0	$ 0	$ 3,250	$ 4			$ 462,684			$ (465,301)
Ending Balance, shares at Dec. 31, 2013		0					7,000	0	0	3,000	4,404,000