Significant Accounting Policies - General (Details) - USD ($) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Liability measured at fair value on a recurring basis
Warrant liability	$ 3,072	$ 1,474
Stock-based compensation vesting period	3 years
Potentially dilutive common stock equivalents excluded from computation (in shares)	3.4	2.3
Fair Value, Inputs, Level 3
Liability measured at fair value on a recurring basis
Warrant liability	$ 3,072	$ 1,474