Amount of letters of credit issued under the credit facility as of the balance sheet date.

No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

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Balance Type:	na
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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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.

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) of the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. 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 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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DEBT Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
DEBT Narrative (Details) - USD ($) $ in Thousands	Feb. 28, 2018	Mar. 31, 2018	Jan. 15, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt		$ 3,656,066		$ 3,613,059
$1.75 billion revolving credit agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 1,750,000
Covenant terms		the maximum allowed consolidated debt coverage ratio (as defined in the Revolving Credit Agreement) to 5.25-to-1.00 for the rolling periods ending June 30, 2018 through December 31, 2018. Subsequently, the maximum allowed consolidated debt coverage ratio may not exceed 5.00-to-1.00 for any rolling periods ending on or after March 31, 2019. As of March 31, 2018, our consolidated debt coverage ratio could not exceed 5.50-to-1.00.
Letters of credit issued		$ 3,700
Current remaining borrowing capacity		804,900
Line of credit facility, increase, net		$ 48,100
Interest rate increase	0.25%
Interest rate at period end - Revolving Credit Agreement		3.60%
Long-term debt		$ 941,400
Logistics Notes due 2018 [Member]
Debt Instrument [Line Items]
Interest rate increase	0.25%
Long-term debt		$ 350,000
Stated interest rate		7.65%
Interest rate at period end		8.65%
Logisitics Notes due 2043 [Member]
Debt Instrument [Line Items]
Long-term debt		$ 402,500
Stated interest rate			7.625%
Interest rate at period end		8.50%
Interest rate terms		an annual rate equal to the sum of the three-month LIBOR rate for the related quarterly interest period, plus 6.734% payable quarterly, commencing with the interest payment due April 15, 2018.
Receivables Financing Agreement [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 125,000
Long-term debt		$ 57,800
Weighted average interest rate		2.80%
Collateral amount		$ 91,800