Summary of Significant Accounting Policies (Details) - Valuation inputs hierarchy classification for the warrant liability measured at fair value on a recurring basis (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Inputs, Level 1 [Member]
Summary of Significant Accounting Policies (Details) - Valuation inputs hierarchy classification for the warrant liability measured at fair value on a recurring basis [Line Items]
Warrant liability
Fair Value, Inputs, Level 2 [Member]
Summary of Significant Accounting Policies (Details) - Valuation inputs hierarchy classification for the warrant liability measured at fair value on a recurring basis [Line Items]
Warrant liability
Fair Value, Inputs, Level 3 [Member]
Summary of Significant Accounting Policies (Details) - Valuation inputs hierarchy classification for the warrant liability measured at fair value on a recurring basis [Line Items]
Warrant liability	$ 2,003	$ 1,474