Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Income Taxes [Line Items]
Income tax payable	$ 1,100			$ 1,100	$ 1,200	$ 2,300
Valuation allowance percentage established for domestic and foreign net deferred tax assets	100.00%			100.00%
Effective income tax rate	21.00%	35.00%			35.00%
Deferred tax assets	$ 118,930			$ 118,930	$ 173,938
Increase (decrease) in valuation allowance	(54,100)
Cumulative amount of undistributed earnings upon which no U.S. income taxes provided	32,400			32,400
Reduction in uncertain tax position due to lapse of various statutes of limitation				$ 10
Subsequent period within which no material changes in unrecognized tax benefits are expected				12 months
Gross unrecognized tax benefits	15,299			$ 15,299	15,819	$ 16,643	$ 17,023
Uncertain tax benefits that, if realized, would affect the effective tax rate	13,100			13,100
Accrued interest and penalties related to uncertain tax positions	40			$ 40	200
Swiss total assessment settlement					$ 100
Minimum
Income Taxes [Line Items]
Statutes of limitations with respect to jurisdictions (in years)				4 years
Maximum
Income Taxes [Line Items]
Statutes of limitations with respect to jurisdictions (in years)				10 years
Scenario Plan
Income Taxes [Line Items]
Deferred tax assets	117,200	$ 171,300		$ 117,200
GILTI tax rate			10.50%
Federal
Income Taxes [Line Items]
Net operating loss carryforwards	329,700			329,700
Federal | Research and development
Income Taxes [Line Items]
Tax credits	18,900			18,900
State
Income Taxes [Line Items]
Net operating loss carryforwards	146,800			146,800
State | Research and development
Income Taxes [Line Items]
Tax credits	$ 19,200			$ 19,200