Income Tax Expense (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory rate	$ (20,315)	$ (11,043)	$ (5,467)
State income tax expense (benefit), net of federal benefit	(937)	(1,097)	73
Meals and entertainment	328	279	298
Research and development credits	(1,756)	(4,897)	0
Stock-based compensation	1,633	1,161	546
Contingent consideration	34	(2,696)	2,890
Foreign tax rate differential	1,013	1,418	656
Net change in valuation allowance	10,052	8,930	2,417
Return to provision true-up	583	593	(1,347)
Unrecognized tax benefits	928	6,444	0
Other, net	(900)	846	(76)
Income tax benefit	$ (9,337)	$ (62)	$ (10)