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Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Valuation allowance
Provision for (benefit from) income taxes	$ 334	$ 4,372	$ 1,297	$ 4,681
Unrecognized tax benefits	125,900		125,900		$ 115,700
Portion of unrecognized tax benefits, which if recognized, would be recorded as an income tax benefit	3,000		3,000
Foreign tax authority
Valuation allowance
Income taxes paid	5,100	$ 4,500	9,600	$ 8,800
State and Local Jurisdiction [Member] \| California Franchise Tax Board \| Research and development tax credit carryforward
Valuation allowance
Valuation allowance, deferred tax asset, increase (decrease)	(700)		(700)
Long-term deferred tax assets
Valuation allowance
Unrecognized tax benefits	23,400		23,400		22,800
Other assets \| Foreign tax authority
Valuation allowance
Unrecognized tax benefits	99,500		99,500		91,000
Long-term income taxes payable
Valuation allowance
Unrecognized tax benefits	$ 3,000		$ 3,000		$ 1,800