Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Effective Income Tax Rate Reconciliation, Amount
Income tax benefit using U.S. federal statutory rate	$ (17,929)	$ (14,241)
State income taxes, net of federal benefit	(270)	(296)
Other permanent differences	(304)	2,985
Foreign rate differential	6,615	3,836
Tax credits	(795)	(223)
Other items	(811)	503
Tax benefit related to the IPR&D transfer	(185)	(185)
IPR&D impairment charge benefit	(434)
Foreign withholding taxes	37	101
Net change in valuation allowance	13,532	7,477
Income tax expense (benefit)	$ (544)	$ (43)