DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Changes in Value Recognized in OCI (Details) - Cash Flow Hedge - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Losses reclassified from AOCI to income
(Loss) Gain Recognized in OCI on Derivatives	$ (5,764)	$ 1,052	$ (11,995)	$ 1,052
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(3,038)	(3,037)	(9,113)	(7,846)
Interest rate contracts
Losses reclassified from AOCI to income
(Loss) Gain Recognized in OCI on Derivatives	(2,207)	1,052	(12,670)	1,052
Commodity derivatives
Losses reclassified from AOCI to income
(Loss) Gain Recognized in OCI on Derivatives	(3,557)	0	675	0
Interest and debt expense \| Interest rate contracts
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(3,038)	(3,037)	(9,113)	(9,112)
Product sales \| Commodity derivatives
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	$ 0	$ 0	$ 0	$ 1,266

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

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=84234895&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=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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