Income Taxes - Rollforward of Unrecognized Tax Benefits (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]
Beginning balance		$ 16,350	$ 16,248	$ 2,039
Additions for tax positions relating to the current year		1,158	1,209	845
Additions for tax positions relating to prior years		0	582	13,389
Reductions for tax positions relating to prior years		(224)	(60)	(25)
Reductions for settlements with taxing authorities		(900)	(1,629)	0
Ending balance		16,384	16,350	16,248
Interest and penalties not included above:
Interest expense (income), net of tax effect, and penalties	[1]	38	(21)	118
Accrued interest and penalties, net of tax effect, at end of year	[1]	$ 208	$ 170	$ 191

[1] Included in income tax expense in the Consolidated Statements of Income.