Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Debt Instrument [Line Items]
Total debt	$ 1,846,294	$ 1,686,189	$ 1,752,757
Less: Current maturities of long-term debt and short-term facilities	(290,048)	(180,036)	(177,430)
Long-term debt	1,556,246	1,506,153	1,575,327
Revolving Facility, Due 2021
Debt Instrument [Line Items]
Total debt	210,000	160,000	30,000
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Total debt	299,579	299,483	299,201
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124,112	124,090	124,024
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	227,989	227,975	227,933
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	395,392	395,252	394,843
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Total debt	298,878	299,033	298,837
Term Loan Facility, Due 2018
Debt Instrument [Line Items]
Total debt			217,109
Trade Receivable Facility
Debt Instrument [Line Items]
Total debt	290,000	180,000	159,925
Other Notes
Debt Instrument [Line Items]
Total debt	$ 344	$ 356	$ 885

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: 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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. 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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts 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.

+ References

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-Name Accounting Standards Codification
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-Section S99
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