Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Stockholders' equity
Series I redeemable preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Series I redeemable preferred stock, shares issued	35,541	119,760
Series I redeemable preferred stock, shares outstanding	35,541	119,760
Series I redeemable preferred stock, liquidation preference	$ 167	$ 167
Common stock, par value (in dollars per share)	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	27,786,655	3,770,113
Common stock, shares outstanding	27,786,427	3,769,712
Treasury stock, shares	228	401
Series A Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	500,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
liquidation preference	$ 0.0001	$ 0.0001
Series J Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001
Preferred stock, shares authorized	1,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
liquidation preference	$ 0.0001
Series B Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 1
Preferred stock, shares issued	1
Preferred stock, shares outstanding	0
liquidation preference	$ 0.0001
Series C Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	1	1
liquidation preference	$ 0.0001	$ 0.0001
Series D Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	4,725	1,227,582
Preferred stock, shares outstanding	4,725	1,227,582
liquidation preference	$ 0.0001	$ 0.0001
Series D-1 Preferred [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	68,638	59,265
Preferred stock, shares outstanding	68,638	59,265
liquidation preference	$ 0.0001	$ 0.0001
Series E Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
liquidation preference	$ 0.0001	$ 0.0001
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
liquidation preference	$ 0.0001	$ 0.0001
Series F-1 Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	0	156,250
Preferred stock, shares outstanding	0
liquidation preference	$ 0.0001	$ 0.0001
Series H Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued	459,043
Preferred stock, shares outstanding	439,043
liquidation preference	$ 0.0001	$ 0.0001