Warrants (Details)	1 Months Ended	6 Months Ended
	Jul. 31, 2015 shares	Jun. 30, 2015 $ / shares shares	Nov. 20, 2014 $ / shares shares	Dec. 31, 2009 $ / shares shares	Dec. 31, 2007 $ / shares shares
Class of Stock [Line Items]
Warrants outstanding (in shares)					24,538
Warrants exercise price (in dollars per share) | $ / shares					$ 0.0978
Credit Agreement
Class of Stock [Line Items]
Warrants outstanding (in shares)		376,691
Warrants exercise price (in dollars per share) | $ / shares		$ 2.3229
B
Class of Stock [Line Items]
Warrants outstanding (in shares)				33,742
Warrants exercise price (in dollars per share) | $ / shares				$ 1.8908
E
Class of Stock [Line Items]
Warrants outstanding (in shares)			429,440
Warrants exercise price (in dollars per share) | $ / shares			$ 0.0163
Liquidation prefence change (as a percent)		2
Subsequent Event | Common stock | E
Class of Stock [Line Items]
Stock issued upon conversion (in shares)	429,042