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RISK MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES, Part 2 (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 USD ($) Bcf MMBbls | Dec. 31, 2020 USD ($) MMBbls Bcf
Derivative [Line Items] |  |
Cash posted - offsetting derivative net liability positions under master-netting arrangements | $ | $ 54.4 | $ 35.1
Derivatives designated as Hedging Instrument | Futures | - Natural gas (Bcf) | Fixed price | Net Purchasor, Sellor |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | Bcf | (80.9) | (43.3)
Derivatives designated as Hedging Instrument | Futures | - Natural gas (Bcf) | Basis | Net Purchasor, Sellor |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | Bcf | (80.9) | (43.3)
Derivatives designated as Hedging Instrument | Futures | - Crude oil and NGLs (MMBbl) | Fixed price | Net Purchasor, Sellor |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | MMBbls | (10.9) | (4.6)
Derivatives designated as Hedging Instrument | Interest Rate Contracts | Net Purchasor, Sellor |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ | $ 1,100.0 | $ 1,100.0
Derivatives not designated as hedging instruments | Futures | - Crude oil and NGLs (MMBbl) | Fixed price | Purchased/ Payor |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | MMBbls | 0.5 | 0.8
Derivatives not designated as hedging instruments | Futures | - Crude oil and NGLs (MMBbl) | Fixed price | Sold/ Receiver |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | MMBbls | (0.5) | (0.8)
Forecasted Debt Issuances [Member] | Cash Flow Hedging [Member] | Forward contracts | Interest Rate Contracts |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ | $ 1,100.0 | $ 1,100.0

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