Income Taxes - Computed Amount and Differences in Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Pretax income	$ 532,903	$ 528,939	$ 455,273
Computed amount at statutory rate	111,910	111,077	159,346
State and local income tax (net of federal tax benefit)	8,163	8,280	5,841
Taxes on non-U.S. earnings-net of foreign tax credits	5,003	5,725	(24,914)
Global Intangible Lowed-Taxed Income	2,324	2,725	0
Foreign-Derived Intangible Income Deduction	(5,811)	(5,410)	0
Effect of flow-through entities	1,316	1,215	192
U.S. business tax credits	(3,193)	(3,056)	(1,928)
Domestic activities production deduction	0	0	(8,516)
Capital loss on divestitures	0	0	(2,275)
Share-based payments	(11,011)	(9,348)	(6,844)
Valuation allowance	(117)	0	(361)
Impact of Tax Act	(334)	10,298	(100)
Other	(868)	(3,140)	(2,425)
Total provision for income taxes	$ 107,382	$ 118,366	$ 118,016