Supplemental Financial Information - Noncash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Condensed Financial Statements, Captions [Line Items]
Accrued but unpaid capital expenditures at period end	$ 3,338	$ 65,286
Common stock withheld for payroll tax obligations	481	181
Cash interest payments	60,253	53,433
Foreign [Member]
Cash income taxes paid, net of (refunds):
Cash income taxes paid, net of refunds	37,884	33,479
State [Member]
Cash income taxes paid, net of (refunds):
Cash income taxes paid, net of refunds	$ 94	$ 1