Income Taxes Narrative (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Tax Credit Carryforward [Line Items]
Benefit for income taxes	$ 2,100	$ (2,400)	$ 6,300	$ 2,400	$ 6,323	$ 1,323	$ 5,818
Current					59	1,719	7,281
Unrecognized tax benefits	27,286			$ 19,076	27,286	19,076	19,121	$ 26,419
Unrecognized tax benefits that would impact effective tax rate if recognized	300				300
Reversal of valuation allowance, foreign taxes					100	45	$ 7,298
Federal
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	139,100				139,100
Federal research and development credit carryforwards	30,300				30,300
Domestic
Tax Credit Carryforward [Line Items]
Domestic state net operating loss carryforwards	156,100				156,100
Federal research and development credit carryforwards	17,700				17,700
Foreign Tax Authority
Tax Credit Carryforward [Line Items]
Income tax refund						$ 1,700
Stock Option Deductions | Federal
Tax Credit Carryforward [Line Items]
Operating loss carryforwards	$ 10,500				$ 10,500