Income Taxes - Reconciliation of Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 41,110	$ 36,229	$ 35,240
Additions based on tax positions related to the current year	7,708	6,231	7,040
Additions for tax positions of prior years	1,200	9,377	3,372
Reductions for tax positions of prior years	0	(2,870)	(1,171)
Reductions for audit settlements	(3,205)	0	0
Reductions resulting from a lapse of the applicable statute of limitations periods	(5,935)	(7,857)	(8,252)
Balance at end of year	$ 40,878	$ 41,110	$ 36,229