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

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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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

+ Details

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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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Long-Term Debt (Detail) - USD ($) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended		6 Months Ended
Long-Term Debt (Detail) - USD ($) $ in Thousands	Apr. 16, 2018	Jun. 30, 2018	May 29, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt - principal		$ 2,977,311		$ 2,977,311	$ 3,112,076	$ 2,977,311	$ 3,112,076	$ 2,564,270
Less unamortized debt issuance costs		14,639		14,639	18,314	14,639	18,314	16,979
Debt long term and short term less unamortized debt issuance costs combined amount		2,962,672		2,962,672	3,093,762	2,962,672	3,093,762	2,547,291
Less current portion		788,731		788,731	648,850	788,731	648,850	108,789
Long-term debt		$ 2,173,941		2,173,941	2,444,912	2,173,941	2,444,912	2,438,502
Loss on early extinguishment of debt				2,493	4,375	2,493	7,052
Term Loans and Revolving Loans Maintained as Base Rate or Canadian Prime Rate Loans [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.50%
Term Loans and Revolving Loans Maintained as Base Rate or Canadian Prime Rate Loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.50%	1.00%
Term Loans And Revolving Loans Maintained as Eurodollar Rate, Euro Rate or CDOR Rate Loans [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.50%
Term Loans And Revolving Loans Maintained as Eurodollar Rate, Euro Rate or CDOR Rate Loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.50%	2.00%
Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal		$ 1,617,851		1,617,851	1,489,971	1,617,851	1,489,971	903,945
5% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Total debt - principal		0		0	280,000	0	280,000	280,000
5 1/2% Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Total debt - principal		300,000		300,000	300,000	300,000	300,000	300,000
4 3/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Total debt - principal		300,000		300,000	300,000	300,000	300,000	300,000
3 1/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Total debt - principal		$ 759,460		759,460	742,105	759,460	742,105	780,325
Revolving Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.30%
Revolving Loan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.30%	0.35%
Revolving Loan [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal		$ 760,000		760,000	609,593	760,000	609,593	0
Less current portion		760,000		760,000		760,000
U S Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal		800,000		800,000	800,000	800,000	800,000	800,000
Canadian Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal		22,937		22,937	35,021	22,937	35,021	27,147
Other Foreign Bank Revolving And Term Loans [Member] \| Bank debt [Member]
Debt Instrument [Line Items]
Total debt - principal		34,914		34,914	$ 45,357	34,914	$ 45,357	$ 76,798
Less current portion		$ 28,700		$ 28,700		$ 28,700
Senior Notes [Member] \| 5% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)		5.00%		5.00%	5.00%	5.00%	5.00%	5.00%
Early Repayment of Senior Debt	$ 280,000
Debt Instrument, Redemption Price, Percentage Plus Accrued and Unpaid Interest	100.00%
Senior Notes [Member] \| 5 1/2% Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)		5.50%		5.50%	5.50%	5.50%	5.50%	5.50%
Senior Notes [Member] \| 4 3/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)		4.75%		4.75%	4.75%	4.75%	4.75%	4.75%
Senior Notes [Member] \| 3 1/4% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note interest rate (percent)		3.25%		3.25%	3.25%	3.25%	3.25%	3.25%
Revolving And Term Loans [Member] \| 5% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Loss on early extinguishment of debt				$ 2,500
Debt Instrument, Redemption, December 31, 2019 \| Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				5.00%
Debt Instrument, Redemption, December 31, 2020 \| Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				10.00%
Debt Instrument, Redemption, December 31, 2021 \| Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				10.00%
Debt Instrument, Redemption, December 31, 2022 \| Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				10.00%
Debt Instrument, Redemption, December 31, 2023 \| Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				10.00%