Long Term Debt (Parenthetical) (Detail)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Maturity date	2018
Interest rate on notes	6.60%
Interest rate	6.81%
7% Debentures, Due 2025
Debt Instrument [Line Items]
Maturity date	2025
Interest rate on notes	7.00%
Interest rate	7.12%
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Maturity date	2037
Interest rate on notes	6.25%
Interest rate	6.45%
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Maturity date	2024
Interest rate on notes	4.25%
Interest rate	4.25%
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity date	2017
Interest rate	1.33%
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Maturity date	2018	2018
Interest rate	1.67%	1.67%
Trade Receivable Credit Facility
Debt Instrument [Line Items]
Credit Facility interest rate		0.77%

Debt instrument maturity date year.

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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 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: 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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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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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- Definition

The effective interest rate at the end of the reporting period.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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