Supplemental Cash Flow Information - Supplemental Cash Flow Information (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net cash provided from operating activities included:
Income taxes refunded from taxing authorities		$ 7,521	$ 1,024	$ 102
Interest paid		(207,433)	(179,431)	(159,875)
Non-cash investing and financing activities included:
Asset retirement costs capitalized, net	[1]	28,826	20,245	(24,064)
(Decrease) increase in accrued capital expenditures		$ (119,021)	$ 71,739	$ 61,419

[1] Includes cost incurred whether capitalized or expensed.