Long-Term Debt (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Total debt - principal	$ 1,946,012	$ 1,525,818	$ 1,984,089
Unamortized debt issuance costs	10,915	12,271	13,587
Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount	1,935,097	1,513,547	1,970,502
Current portion	569,892	152,398	532,639
Long-term debt	1,365,205	1,361,149	1,437,863
Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	1,146,012	725,818	1,184,089
5 1/2% Senior Notes [Member]
Debt Instrument [Line Items]
Total debt - principal	300,000	300,000	300,000
5% Senior Notes [Member]
Debt Instrument [Line Items]
Total debt - principal	500,000	500,000	500,000
Revolving Loan [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 416,501	$ 0	$ 407,000
Senior Notes [Member] \| 5 1/2% Senior Notes [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)	5.50%	5.50%	5.50%
Senior Notes [Member] \| 5% Senior Notes [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)	5.00%	5.00%	5.00%
Bank revolving loans and term loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Current portion	$ 477,500
U S Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	346,750	$ 346,750	$ 365,000
Canadian Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	45,833	47,973	53,493
Euro Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	232,262	227,434	246,994
Other Foreign Bank Revolving And Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	104,666	$ 103,661	$ 111,602
Current portion	$ 92,400

Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount

No definition available.

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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 FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

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

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- Definition

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

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

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ 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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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