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ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Comprehensive (Income) Loss Before Reclassification, Retirement and Other Postretirement Benefit Plan Obligations | $ (19,490) | $ (8,116) |
Other Comprehensive Income (Loss) Before Reclassification, Risk-Management Assets/Liabilities of Unconsolidated Affiliates | (7,275) | 2,396 |
Other comprehensive income (loss) before reclassifications | (174,568) | (11,393) |
Other Comprehensive Income (Loss), Risk-Management Assets/Liabilities, after Reclassification Adjustment, after Tax | (168,860) |  |
Change in fair value of derivatives, net of tax | (147,803) | (5,673) | $ (21,408)
Other comprehensive Income (Loss) Reclassification Adjustment from AOCI for Risk-Management Assets/Liabilities, Net of Tax | (21,057) | 36,870 | 63,687
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Other Comprehensive Income Attributable to Unconsolidated Affiliates, Net of Tax | (70) | (28) |
Other comprehensive Income (Loss), Reclassification Adjustment included in Net Income, Net of Tax | (11,193) | 49,785 | 53,867
Other Comprehensive Income (Loss), Risk-management Assets/Liabilities, after Reclassification, Adjustment, Net of Tax, Portion Attributable to Parent |  | 31,197 |
Other Comprehensive (Income) Loss, Retirement and Other Postretirement Benefit Plans, after Reclassification Adjustment, after Tax | (9,696) | 4,771 | (4,175)
Other comprehensive income (loss) Risk-Management Assets/Liabilities of unconsolidated affiliates | (7,205) | 2,424 | (970)
Other Comprehensive Income (Loss), Net of Tax | (185,761) | 38,392 | 37,134
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent |  | 38,392 |
Impact of Adoption of ASU 2018-02 on Unrealized Gains (Losses) on Risk Management Assets/Liabilities |  | (17,020) |
Impact of Adoption of ASU 2018-02 on Retirement and Other Postretirement Benefit Plan Obligations |  | (20,340) |
Impact of Adoption of ASU 2018-02 on Unrealized Gains (Losses) on Risk Management Assets/Liabilities of Unconsolidated Affiliates |  | (741) |
Impact of Adoption of ASU 2018-02 on AOCI, Total |  | (38,101) |
Risk management assets/liabilities - December 31 | (233,520) | (64,660) | (81,915)
Retirement and Other Postretirement Benefit Plan Obligations - December 31 | (131,481) | (121,785) | (105,411)
Risk-management assets/liabilities of unconsolidated affiliates - December 31 | (8,999) | (1,794) | (1,204)
Accumulated other comprehensive loss - December 31 | (374,000) | (188,239) | (188,530)
Beginning balance adjustments on Risk management assets/liabilities |  |  | 3,078
Beginning balance adjustments on retirement and other postretirement benefit plan obligations |  |  | (805)
Beginning balance adjustments on risk-management asset/liabilities of unconsolidated affiliates |  |  | (2,273)
Beginning balance adjustments on accumulated other comprehensive loss |  |  | 0
Reclassification Adjustment from AOCI on Risk Management Assets/Liabilities, Income Tax | (6,058) | 11,013 | 26,899
Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months | 28,900 |  |
Commodity Cash Flow Hedge Gain (Loss) To Be Reclassified After Next 12 Months Net | (800) |  |
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net | (20,300) |  |
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] |  |  |
Other comprehensive Income (Loss) Reclassification Adjustment from AOCI for Risk-Management Assets/Liabilities, Net of Tax |  |  | 45,541
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Sales [Member] | Commodity Contract [Member] |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | 50,345 | (29,596) | (69,561)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Interest Expense [Member] | Interest Rate Contracts |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | (23,230) | (18,287) | (21,025)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Total before tax [Member] |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | 27,115 | (47,883) | (90,586)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Tax Expense [Member] |  |  |
Reclassification Adjustment from AOCI on Risk Management Assets/Liabilities, Income Tax | (6,058) | 11,013 | 26,899
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Net of tax [Member] |  |  |
Other comprehensive Income (Loss) Reclassification Adjustment from AOCI for Risk-Management Assets/Liabilities, Net of Tax | (21,057) | 36,870 | 63,687
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] | Net income attributable to noncontrolling interest [Member] |  |  |
Reclassification Adjustment from AOCI on Risk Management Assets/Liabilities Net of Tax, Portion Attributable to Noncontrolling Interest | 0 | 0 | (18,146)
Accumulated Retirement and Other Postretirement Benefit Plans Adjustment Attributable to Parent [Member] |  |  |
Other Comprehensive (Income) Loss, Retirement and Other Postretirement Benefit Plans, Reclassification Adjustment from AOCI, After Tax | (9,794) | (12,887) | (8,162)
Retirement and Other Postretirement Benefit Plans, Amortization of Gain (Loss) | (12,946) | (18,398) | (15,265)
Retirement and Other Postretirement Benefit Plans, Amortization of Prior Service Credit | 227 | 1,662 | 1,662
Reclassification Adjustment from AOCI, before Tax, Retirement and Other Postretirement Benefit Plans, Gain (Loss) | (12,719) | (16,736) | (13,603)
Reclassification Adjustment from AOCI, Tax, Retirement and Other Postretirement Benefit Plans, Gain (Loss) | 2,925 | 3,849 | 5,441
Accumulated Other Comprehensive Income from Investments in Unconsolidated Affiliates Attributable to Parent [Member] |  |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Other Comprehensive Income Attributable to Unconsolidated Affiliates, Net of Tax | (70) | (28) | (164)
Reclassification Adjustment from AOCI, Before Tax, Portion Attributable to Unconsolidated Affiliates | (91) | (36) | (367)
Reclassification Adjustment from AOCI, Tax, Portion Attributable to Unconsolidated Affiliates | 21 | 8 | 97
Accumulated Other Comprehensive Income from Investments in Unconsolidated Affiliates Attributable to Parent [Member] | Net of tax [Member] |  |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Other Comprehensive Income Attributable to Unconsolidated Affiliates, Net of Tax | (70) | (28) | (270)
Reclassification Adjustment from AOCI, Net of Tax, Portion Attributable to Noncontrolling Interests | 0 | 0 | (106)
AOCI Attributable to Parent [Member] |  |  |
Other Comprehensive Income (Loss), Net of Tax | (185,761) | 38,392 | 6,108
Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | 27,115 | (47,883) | (90,586)
Cash Flow Hedging [Member] | Commodity Contract [Member] |  |  |
Unrealized Gain Loss On Cash Flow Hedges Net Of Tax Accumulated Other Comprehensive Income Loss | 28,119 |  |
Cash Flow Hedging [Member] | Interest Rate Contracts |  |  |
Amount of accumulated other comprehensive income (loss) attributable primarily to settled interest-rate swaps. | (106,592) |  |
Cash Flow Hedging [Member] | Forward Contracts [Member] |  |  |
Amount of accumulated other comprehensive income (loss) attributable primarily to forward starting interest-rate swaps. | (155,047) |  |
Cash Flow Hedging [Member] | Sales [Member] | Commodity Contract [Member] |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | 50,345 | (29,596) | (69,561)
Cash Flow Hedging [Member] | Interest Expense [Member] | Interest Rate Contracts |  |  |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income | $ (23,230) | $ (18,287) | $ (21,025)

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