Income Taxes - Difference Between Total Tax Expense and Amount Computed by Applying Statutory Federal Income Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Statutory rate applied to income	$ 174,363	$ 225,879	$ 353,259
Plus state income taxes, net of Federal tax benefit	27,305	35,626	27,918
Taxation of foreign operations, net	(18,331)	(7,639)	(33,984)
U.S. tax reform - transition tax	4,492	4,875	37,132
Book tax basis difference in investment	0	(11,944)	0
Valuation allowance	4,745	20,505	1,273
Other	10,426	(1,127)	2,397
Income tax expense, total	209,215	265,138	392,511
Domestic Tax Authority
Income Tax Contingency [Line Items]
Deferred tax remeasurement	0	424	13,854
Foreign Tax Authority
Income Tax Contingency [Line Items]
Deferred tax remeasurement	$ 6,215	$ (1,461)	$ (9,338)