Commitments and Guarantees Unrecorded Unconditional Purchase Obligations (Details) $ in Millions	Dec. 31, 2024 USD ($)
Capital Addition Purchase Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 847
Unrecorded Unconditional Purchase Obligation, Due within One Year	564
Unrecorded Unconditional Purchase Obligation, Due within Two Years	147
Unrecorded Unconditional Purchase Obligation, Due within Three Years	82
Unrecorded Unconditional Purchase Obligation, Due within Four Years	12
Unrecorded Unconditional Purchase Obligation, Due within Five Years	2
Unrecorded Unconditional Purchase Obligation, Due after Five Years	40
Long-term Contract for Purchase of Electric Power [Domain]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	5,068
Unrecorded Unconditional Purchase Obligation, Due within One Year	560
Unrecorded Unconditional Purchase Obligation, Due within Two Years	458
Unrecorded Unconditional Purchase Obligation, Due within Three Years	347
Unrecorded Unconditional Purchase Obligation, Due within Four Years	351
Unrecorded Unconditional Purchase Obligation, Due within Five Years	343
Unrecorded Unconditional Purchase Obligation, Due after Five Years	3,009
Electric Transmission [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	1,062
Unrecorded Unconditional Purchase Obligation, Due within One Year	186
Unrecorded Unconditional Purchase Obligation, Due within Two Years	218
Unrecorded Unconditional Purchase Obligation, Due within Three Years	128
Unrecorded Unconditional Purchase Obligation, Due within Four Years	129
Unrecorded Unconditional Purchase Obligation, Due within Five Years	130
Unrecorded Unconditional Purchase Obligation, Due after Five Years	271
Public Utility Districts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	52
Unrecorded Unconditional Purchase Obligation, Due within One Year	11
Unrecorded Unconditional Purchase Obligation, Due within Two Years	10
Unrecorded Unconditional Purchase Obligation, Due within Three Years	9
Unrecorded Unconditional Purchase Obligation, Due within Four Years	7
Unrecorded Unconditional Purchase Obligation, Due within Five Years	1
Unrecorded Unconditional Purchase Obligation, Due after Five Years	14
Natural gas [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	494
Unrecorded Unconditional Purchase Obligation, Due within One Year	109
Unrecorded Unconditional Purchase Obligation, Due within Two Years	89
Unrecorded Unconditional Purchase Obligation, Due within Three Years	45
Unrecorded Unconditional Purchase Obligation, Due within Four Years	44
Unrecorded Unconditional Purchase Obligation, Due within Five Years	30
Unrecorded Unconditional Purchase Obligation, Due after Five Years	177
Coal and transportationSupply Agreements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	27
Unrecorded Unconditional Purchase Obligation, Due within One Year	27
Unrecorded Unconditional Purchase Obligation, Due within Two Years	0
Unrecorded Unconditional Purchase Obligation, Due within Three Years	0
Unrecorded Unconditional Purchase Obligation, Due within Four Years	0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	0
Unrecorded Unconditional Purchase Obligation, Due after Five Years	0
Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	7,550
Unrecorded Unconditional Purchase Obligation, Due within One Year	1,457
Unrecorded Unconditional Purchase Obligation, Due within Two Years	922
Unrecorded Unconditional Purchase Obligation, Due within Three Years	611
Unrecorded Unconditional Purchase Obligation, Due within Four Years	543
Unrecorded Unconditional Purchase Obligation, Due within Five Years	506
Unrecorded Unconditional Purchase Obligation, Due after Five Years	$ 3,511

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

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- Definition

Amount of unrecorded obligation to transfer funds in future for fixed or minimum amount or quantity of product and service at fixed or minimum price. Includes, but is not limited to, lease not yet commenced and take-or-pay and throughput contracts.

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

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