DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Changes in Value Recognized in OCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Interest rate contracts
Losses reclassified from AOCI to income
Cash flow hedge loss to be reclassified within twelve months	$ 12,200
Cash Flow Hedge
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(1,772)	$ (3,037)
Interest and debt expense \| Cash Flow Hedge \| Interest rate contracts
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(3,038)	(3,037)
Product sales \| Cash Flow Hedge \| Commodity derivatives
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	$ 1,266	$ 0

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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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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