Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

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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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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Detail) - USD ($)		3 Months Ended
Debt - Additional Information (Detail) - USD ($)	Mar. 20, 2017	Mar. 31, 2017	Mar. 31, 2016
Debt Instrument [Line Items]
Repayment of debt		$ 340,000,000	$ 70,000,000
Revolver
Debt Instrument [Line Items]
Line of credit facility remaining borrowing capacity		$ 784,000,000
Series G senior notes 3.875% due April 2024
Debt Instrument [Line Items]
Face amount of debt	$ 400,000,000
Debt interest rate	3.875%
Proceed from issuance of note	$ 395,000,000
Frequency of interest payable		Interest is payable semi-annually.
Date of first payment	Nov. 15, 2017
Maturity date	Apr. 01, 2024
Series G senior notes 3.875% due April 2024 \| Revolver
Debt Instrument [Line Items]
Repayment of debt	$ 250,000,000