Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2014

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013 are as follows:

($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of March 31, 2014		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	57,887	$	57,887	$	—	$	—
Warrant liability	$	11,694	$	—	$	11,694	$	—

($ in thousands)			Fair Value Measurements at Reporting Date Using
Description	Balance as of December 31, 2013		Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash equivalents	$	66,974	$	66,974	$	—	$	—
Warrant liability	$	11,776	$	—	$	11,776	$	—