Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Accrued liabilities	$ 1,777	$ 649
Stock-based compensation	7,737	6,401
Net operating loss carryovers	18,609	23,241
Research tax credit carryovers	7,931	4,596
Other	1,926	1,357
Total deferred tax assets	37,980	36,244
Less valuation allowance	(29,255)	(32,481)
Deferred tax assets, net of valuation allowance	8,725	3,763
Deferred Tax Liabilities:
Fixed assets	(2,630)	(777)
Intangible assets	(12,198)	(3,036)
Other	0	0
Total deferred tax liabilities	(14,828)	(3,813)
Net deferred tax assets	$ (6,103)	$ (50)