Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
USD Interest Rate Swap Contract One [Member]
Derivative [Line Items]
Notional principal amount of outstanding of the interest rate swap agreement	$ 50,000
Fixed interest rate	2.878%
USD Interest Rate Swap Contract Two [Member]
Derivative [Line Items]
Notional principal amount of outstanding of the interest rate swap agreement	$ 50,000
Fixed interest rate	2.878%
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	$ 174,540
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	626
Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	174,540
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	626
Bank debt [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,268,497
Bank debt [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,268,497
5% Senior Notes [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	280,000
5% Senior Notes [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	280,162
5 1/2% Senior Notes [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	300,000
5 1/2% Senior Notes [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	306,195
4 3/4% Senior Notes due 2025 [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	300,000
4 3/4% Senior Notes due 2025 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	291,585
3 1/4% Senior Notes due 2025 [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	801,060
3 1/4% Senior Notes due 2025 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	$ 817,105
5% Senior Notes due 2020 [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.00%	5.00%	5.00%
5% Senior Notes due 2020 [Member] | Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.00%
5 1/2% Senior Notes due 2022 [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.50%	5.50%	5.50%
5 1/2% Senior Notes due 2022 [Member] | Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.50%
3 1/4% Senior Notes due 2025 [Member]
Derivative [Line Items]
Senior note interest rate (percent)	3.25%	3.25%	3.25%
4 3/4% Senior Notes due 2025 [Member]
Derivative [Line Items]
Senior note interest rate (percent)	4.75%	4.75%	4.75%
Accumulated Translation Adjustment [Member]
Derivative [Line Items]
Foreign currency (losses) of net investment hedges included in accumulated other comprehensive loss	$ (9,600)