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v3.22.1

Risk Management Activities (Narrative) (Details) mMDth in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) mMDth | Dec. 31, 2021 USD ($) mMDth
Derivative [Line Items] |  |
Limit of GCA Volumes | 20.00% |
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net | $ 0.0 | $ 0.0
Minimum |  |
Derivative [Line Items] |  |
Commodity Contract Length | 1 year |
Maximum |  |
Derivative [Line Items] |  |
Commodity Contract Length | 5 years |
Interest Rate Swap |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ 500.0 |
Natural Gas |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | mMDth | 117.2 | 124.5

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