Fair Value Measurements (Changes in Liabilities Measured at Fair Value Using Significant Unobservable Inputs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Opening balance	$ 4,083	$ 7,612	$ 0
Derivative warrants issued to I/P’s shareholders in connection with the Merger			21,954
Fair value of derivative warrants issued			3,162
Net impact of removal of down-round clause in Series 1 Warrant		(2,300)
Fair value adjustment, prior to exercise of warrants, included in consolidated statement of operations	56	9	156
Exercise of derivative warrants	(1,707)	(808)	(10,657)
Fair value adjustment at end of period, included in consolidated statement of operations	(2,257)	(430)	(7,003)
Closing balance	$ 175	$ 4,083	$ 7,612