Stock Purchase Warrants (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended
	Oct. 10, 2014	Oct. 25, 2012	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value Adjustment of Warrants			$ 3,895	$ 0	$ 8,047	$ 0
Warrant liabilities			$ 14,803		$ 14,803		$ 6,756
Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance Of Warrants To Purchase Of Common Stock		635,855
Warrants Exercisable Price Per Share		$ 1.60
Investment Warrants Expiration Date1		Oct. 25, 2017
Class of Warrant or Right, Outstanding			316,522		316,522
Stock Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from Issuance of Common Stock	$ 19,100
Sale of Stock, Number of Shares Issued in Transaction	14,059,616
Sale of Stock, Price Per Share	$ 1.47
Issuance Of Warrants To Purchase Of Common Stock	0.5
Share Based Compensation Arrangement By Share Based Payment Award Warrants Exercisable Number	7,029,808
Warrants Exercisable Price Per Share	$ 1.75
Warrant liabilities			$ 14,800		$ 14,800
Investment Warrants Expiration Date1	Oct. 10, 2019
Stock Warrants [Member] | Non Cash Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair Value Adjustment of Warrants			$ 3,900		$ 8,100