Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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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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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Gross amount of debt extinguished.

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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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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Topic 230

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Debt - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended	6 Months Ended
	Jun. 15, 2015	May. 15, 2015	Jun. 30, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Net borrowings under revolver portion of credit facility				$ 250
Revolving Credit Facility
Debt Instrument [Line Items]
Net borrowings under revolver portion of credit facility			$ 80
Amount of borrowing capacity currently available under the credit facility			$ 730	$ 730
Series E senior notes 4% due June 2025
Debt Instrument [Line Items]
Face amount of debt		$ 500
Debt interest rate		4.00%	4.00%	4.00%
Proceed from issuance of note		$ 495
Effective interest rate with hedge		3.93%
Series X senior notes 5.875% due 2019
Debt Instrument [Line Items]
Debt interest rate	5.875%
Repayment of debt	$ 500
Redemption price of senior notes	$ 515