Income Taxes - Components of Provision and Current Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Cuts and Jobs Act of 2017
Corporate tax rate (as a percent)		21.00%	21.00%	35.00%
Additional income tax expense from on-time revaluation of certain tax-related assets	$ 47,600
Current:
Federal		$ 56,450	$ 69,477	$ 101,162
State and local		23,796	27,909	24,595
Total current		80,246	97,386	125,757
Deferred:
Federal		14,047	(2,043)	58,732
State and local		3,013	(1,559)	184
Total deferred		17,060	(3,602)	58,916
Total provision for income taxes		97,306	93,784	$ 184,673
Receivables
Current income tax receivable due from various jurisdictions		$ 24,400	$ 25,300