Long-Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Debt Instrument [Line Items]
Total debt - principal	$ 1,828,674	$ 1,525,818	$ 1,931,814
Less unamortized debt issuance costs	10,263	12,271	12,924
Debt Long Term and Short Term Less Unamortized Debt Issuance Expense Combined Amount	1,818,411	1,513,547	1,918,890
Current portion	454,212	152,398	482,877
Long-term debt	1,364,199	1,361,149	1,436,013
Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	1,028,674	725,818	1,131,814
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	$ 306,557	$ 0	$ 357,044
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	$ 367,800
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	45,393	47,973	49,582
Euro Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	234,853	227,434	246,576
Other Foreign Bank Revolving And Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	95,121	$ 103,661	$ 113,612
Current portion	$ 86,400

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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