Debt Facilities - Interest Charges (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Interest expense	$ 521,494,000	$ 478,698,000	$ 392,156,000
Interest capitalized	19,880,000	22,625,000	13,338,000
Interest charges incurred (1)	541,374,000	501,323,000	405,494,000
Cash paid for interest	$ 476,915,000	$ 422,200,000	$ 336,700,000