Debt - Interest Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Gross interest expense	$ 268,942	$ 328,228	$ 383,098
Amortization of debt premiums, net	(590)	(13,728)	(30,596)
Amortization of debt issuance costs, net	13,243	14,479	15,459
Interest expense before capitalization	281,595	328,979	367,961
Capitalized amounts	(52,454)	(54,493)	(64,815)
Net interest expense	229,141	274,486	303,146
Total cash paid for interest, net of receipts and amounts capitalized	$ 205,485	$ 278,313	$ 322,442