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Risk Management Activities (Narrative) (Details) mMDth in Millions, $ in Millions | Mar. 31, 2024 USD ($) mMDth | Dec. 31, 2023 USD ($) mMDth
--- | --- | ---
Derivative [Line Items] |  |
Limit of GCA Volumes | 20.00% |
Derivative Asset, Subject to Master Netting Arrangement, after Offset | $ | $ 9.7 | $ 13.9
Customer annual demand | 20.00% |
Natural Gas |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | mMDth | 86.0 | 76.1

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