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Derivatives Instruments (Notional Volumes of Outstanding HFT Derivatives) (Details) - HFT derivatives MWh in Millions, MMBTU in Millions | 12 Months Ended
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Dec. 31, 2024 MMBTU MWh
Power | Purchases | 2025 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 1
Power | Purchases | 2026 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Purchases | 2027 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Purchases | 2028 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Purchases | 2029 and thereafter |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Sales | 2025 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 1
Power | Sales | 2026 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Sales | 2027 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Sales | 2028 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Power | Sales | 2029 and thereafter |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MWh | 0
Natural gas | Purchases | 2025 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 262
Natural gas | Purchases | 2026 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 111
Natural gas | Purchases | 2027 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 43
Natural gas | Purchases | 2028 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 30
Natural gas | Purchases | 2029 and thereafter |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 73
Natural gas | Sales | 2025 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 299
Natural gas | Sales | 2026 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 69
Natural gas | Sales | 2027 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 16
Natural gas | Sales | 2028 |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 8
Natural gas | Sales | 2029 and thereafter |
Derivative [Line Items] |
Notional volumes of outstanding derivatives that are expected to settle | MMBTU | 4

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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 + Details
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