Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income tax provision based on the U.S. federal statutory tax rate		$ 45,182	$ 33,893	$ 75,806
Partnership income not subject to corporate income tax		(14,031)	(16,403)	(23,644)
State and local taxes, net		4,906	5,278	4,878
Valuation allowance	$ 2,300	196	2,321	(119)
Tax credits		(1,026)	(1,300)	(1,063)
Change in U.S. tax law		111	(8,730)	(54,171)
Foreign currency translation (gains) losses		(4,707)	7,949	(10,756)
Nondeductible expenses and other		28	135	(929)
Total provision (benefit) for income taxes		$ 30,659	$ 23,143	$ (9,998)