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Risk Management Activities (Narrative) (Details) mMDth in Millions, $ in Millions	Mar. 31, 2025 USD ($) mMDth	Dec. 31, 2024 USD ($) mMDth
Derivative [Line Items]
Limit of GCA Volumes	20.00%
Derivative Asset, Subject to Master Netting Arrangement, after Offset | $	$ 48.1	$ 23.5
Customer annual demand	2000.00%
Minimum
Derivative [Line Items]
Commodity Contract Length	1 year
Maximum
Derivative [Line Items]
Commodity Contract Length	2 years
Natural Gas
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | mMDth	73.3	77.8

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Commodity Contract Length

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Customer annual demand

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Limit of GCA Volumes

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Fair value, after effect of master netting arrangement, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative subject to master netting arrangement not elected or qualified to offset. Excludes derivative not subject to master netting arrangement or similar agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483466/210-20-50-3

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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- Definition

Nominal number of units used to calculate payment on derivative.

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