Income Taxes - Schedule of Provision for Income Taxes with Income Tax at Federal Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	$ 987,162	$ 1,296,802	$ 156,067
Expected income tax provision based on US statutory tax rate	207,304	272,328	54,623
State income taxes, net of federal benefit	31,967	45,920	4,682
Tax benefit from US tax reform legislation	0	0	(713,655)
Tax benefit (deficiency) from stock-based compensation	(7,971)	(259)	3,932
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	8,282	2,932	13,813
Sale of Canadian subsidiary and assets	(16,860)	0	0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	19,600
Other, net	(10,033)	(13,819)	3,225
Provision (benefit) for income taxes	$ 212,689	$ 307,102	$ (633,380)
Federal statutory income tax rate	21.00%	21.00%	35.00%
Effective tax rate	21.50%	23.70%	(405.80%)