Income Taxes - Components Of Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Federal and state net operating losses	$ 115,583	$ 80,549
Research credits	23,353	18,773
Deferred compensation	10,031	14,391
Deferred revenue	8,635	12,176
Accrued expenses	3,023	2,851
Intangibles	3,300	3,441
Depreciation	686	838
Unrealized loss on marketable securities	1	6
Total deferred tax assets	164,612	133,025
Valuation allowance	$ (164,612)	$ (133,025)