Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Fixed interest rate related to the interest rate derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
USD Interest Rate Swap Contract One [Member]
Derivative [Line Items]
Notional principal amount of outstanding of the interest rate swap agreement	$ 50,000	$ 50,000
Fixed interest rate	2.878%	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	$ 50,000
Fixed interest rate	2.878%	2.878%
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	$ 171,369	$ 171,369
Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	171,369	171,369
Bank debt [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,557,478	1,557,478
Bank debt [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,557,478	1,557,478
5 1/2% Senior Notes [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	300,000	300,000
5 1/2% Senior Notes [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	304,089	304,089
4 3/4% Senior Notes due 2025 [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	300,000	300,000
4 3/4% Senior Notes due 2025 [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	287,982	287,982
3 1/4% Senior Notes due 2025 [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	754,260	754,260
3 1/4% Senior Notes due 2025 [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	$ 779,769	$ 779,769
5% Senior Notes due 2020 [Member] \| Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.00%	5.00%	5.00%	5.00%
5 1/2% Senior Notes due 2022 [Member] \| Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.50%	5.50%	5.50%	5.50%
3 1/4% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	3.25%	3.25%	3.25%	3.25%
4 3/4% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	4.75%	4.75%	4.75%	4.75%
Accumulated Translation Adjustment [Member]
Derivative [Line Items]
Foreign currency gains of net investment hedges included in accumulated other comprehensive loss	$ 2,400	$ 12,000