Derivative Financial Instruments (Details 2) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Changes in derivative instrument liability
Balance at the beginning of the period			$ 172		$ 172
Change in fair value of warrants during the quarter	$ (1,446)			$ (425)	364	$ (1,404)
Balance at the end of the period	$ 533				$ 533
Derivative instrument liability | Warrants
Changes in warrants
Balance at the beginning of the period (in shares)			858,469		858,469
Exercise of warrants ( in shares)	(30,000)
Expiration of warrants ( in shares)	(2,469)	(324,000)
Balance at the end of the period (in shares)	502,000				502,000
Changes in derivative instrument liability
Balance at the beginning of the period			$ 172		$ 172
Change in fair value of warrants during the quarter	$ (1,445)	$ 1,541	$ 268
Expiration of warrants	(3)
Balance at the end of the period	$ 533				$ 533