Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Debt Instrument [Line Items]
Total debt - principal	$ 2,192,563	$ 1,571,192	$ 1,829,629
Less unamortized debt issuance costs	20,552	9,609	11,619
Debt long term and short term less unamortized debt issuance costs combined amount	2,172,011	1,561,583	1,818,010
Less current portion	580,247	217,127	449,512
Long-term debt	1,591,764	1,344,456	1,368,498
Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	400,183	771,192	1,029,629
5% Senior Notes due 2020 [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%
5 1/2% Senior Notes due 2022 [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%
4 3/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 300,000	$ 0	$ 0
Senior note interest rate (percent)	4.75%
3 1/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 692,380	0	0
Senior note interest rate (percent)	3.25%
Revolving Loan [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	$ 319,510	99,500	299,031
Less current portion	317,000
Bank Revolving and Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Less current portion	319,500
U S Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	0	310,250	346,750
Canadian Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	34,166	44,274	45,119
Euro Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	0	196,668	233,683
Other Foreign Bank Revolving And Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal	46,507	$ 120,500	$ 105,046
Less current portion	40,700
5% Senior Notes due 2020 [Member] \| 5% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Less current portion	$ 220,000

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

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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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+ References

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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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