Fair Value Measurement and Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Interest rate swap agreements
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carry value	$ 2,476	$ 3,888
Fair value	2,476	3,888
4.375% Senior Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carry value	248,438	248,310
Fair value	$ 266,308	$ 260,265
Stated interest rate (as a percent)	4.375%	4.375%
3.45% Senior Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carry value	$ 747,580	$ 747,474
Fair value	$ 742,808	$ 719,273
Stated interest rate (as a percent)	3.45%	3.45%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.22(a)(1))
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Fair value portion of notes payable.

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