Income Taxes - Reconciliation of Reserve for Uncertain Tax Positions, Excluding Interest and Penalties (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]
Gross balance at January 1,	$ 161,256	$ 174,437	$ 159,826
Additions based on tax positions related to current year	934	97	14,187
Additions for tax positions of prior years	224	25	1,284
Reductions for tax positions of prior years	(28,542)	(12,806)	(860)
Expiration of statutes	(1,629)	(497)	0
Tax settlements	(1,406)	0	0
Gross balance at December 31,	130,837	161,256	174,437
Related tax benefits	(400)	(1,008)	(1,008)
Net reserve at December 31,	$ 130,437	$ 160,248	$ 173,429