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, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Losses reclassified from AOCI to income
Gain Recognized in OCI on Derivatives	$ 1,052	$ 11,168	$ 1,052	$ 7,311
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(3,037)	(3,037)	(7,846)	(9,113)
Interest rate contracts
Losses reclassified from AOCI to income
Gain Recognized in OCI on Derivatives	1,052	0	1,052	0
Commodity derivatives
Losses reclassified from AOCI to income
Gain Recognized in OCI on Derivatives	0	11,168	0	7,311
Interest and debt expense \| Interest rate contracts
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	(3,037)	(3,037)	(9,112)	(9,113)
Product sales \| Commodity derivatives
Losses reclassified from AOCI to income
(Loss) Gain Reclassified from AOCI to Income (Effective Portion)	$ 0	$ 0	$ 1,266	$ 0

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=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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- 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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