Long Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Debt Instrument [Line Items]
Total debt	$ 1,705,152	$ 1,585,395	$ 1,618,275
Less: Current maturities	(147,536)	(14,336)	(14,331)
Long-term debt	1,557,616	1,571,059	1,603,944
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Total debt	299,305	299,123	299,063
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124,524	124,500	124,493
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228,213	228,184	228,175
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	395,614	395,309	395,211
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Total debt	299,251	298,869	298,760
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Total debt	227,121	236,258	239,304
Trade Receivable Facility
Debt Instrument [Line Items]
Total debt	130,000		30,000
Other Notes
Debt Instrument [Line Items]
Total debt	$ 1,124	$ 3,152	$ 3,269

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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