RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES Part 1 (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Derivative, Fair Value [Line Items]
Assets	$ 295,967	$ 110,498
(Liabilities)	(636,462)	(349,018)
Derivative, Net Liability Position, Aggregate Fair Value	0
Cash posted - offsetting derivative net liability positions under master-netting arrangements	194,100	35,100
Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	287,769	107,461
(Liabilities)	(628,292)	(345,980)
Derivatives not designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	8,198	3,037
(Liabilities)	(8,170)	(3,038)
Natural Gas Pipelines
Derivative, Fair Value [Line Items]
Derivative, Fair Value, Net	0	0
Other Current Assets [Member] \| Interest Rate Contracts \| Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	0	0
Other Current Liabilities [Member] \| Interest Rate Contracts \| Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
(Liabilities)	(91,230)	0
Other Deferred Credits \| Interest Rate Contracts \| Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	0	0
(Liabilities)	(55,161)	(203,407)
Fully Netted Assets/Liabilities \| Commodity Contracts \| Financial contracts \| Derivatives designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	287,769	107,461
(Liabilities)	(481,901)	(142,573)
Fully Netted Assets/Liabilities \| Commodity Contracts \| Financial contracts \| Derivatives not designated as hedging instruments
Derivative, Fair Value [Line Items]
Assets	8,198	3,037
(Liabilities)	$ (8,170)	$ (3,038)

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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