Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Debt Instrument [Line Items]
Total debt - principal	$ 1,829,629	$ 1,525,818	$ 1,910,807
Less unamortized debt issuance costs	11,619	12,271	14,234
Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount	1,818,010	1,513,547	1,896,573
Less current portion	449,512	152,398	474,023
Long-term debt	1,368,498	1,361,149	1,422,550
Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	1,029,629	725,818	1,110,807
5 1/2% Senior Notes [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 300,000	$ 300,000	$ 300,000
Senior note interest rate (percent)	5.50%	5.50%	5.50%
5% Senior Notes [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 500,000	$ 500,000	$ 500,000
Senior note interest rate (percent)	5.00%	5.00%	5.00%
Revolving Loan [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 299,031	$ 0	$ 359,500
Bank revolving loans and term loans[Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Less current portion	360,100
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	45,119	47,973	52,515
Euro Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	233,683	227,434	236,192
Other Foreign Bank Revolving And Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	105,046	$ 103,661	$ 97,600
Less current portion	$ 89,400

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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