Income Taxes - Uncertain Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits—beginning balance	$ 93,806	$ 74,436	$ 48,835
Increases related to tax positions taken in a prior year	3,103	11,171	330
Increases related to tax positions taken during current year	20,274	22,714	27,413
Decreases related to tax positions taken in a prior year	(18,029)	(89)	(675)
Decreases related to settlements with taxing authorities	0	(12,388)	0
Decreases related to lapse of statute of limitations	(6,654)	(2,120)	(2,173)
Adjustment for acquisition	0	82	706
Gross unrecognized tax benefits—ending balance	$ 92,500	$ 93,806	$ 74,436