Commitments and Guarantees Unrecorded Unconditional Purchase Obligations (Details) $ in Millions	Dec. 31, 2021 USD ($)
Capital Addition Purchase Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 257
Unrecorded Unconditional Purchase Obligation, Due within One Year	146
Unrecorded Unconditional Purchase Obligation, Due within Two Years	58
Unrecorded Unconditional Purchase Obligation, Due within Three Years	7
Unrecorded Unconditional Purchase Obligation, Due within Four Years	2
Unrecorded Unconditional Purchase Obligation, Due within Five Years	1
Unrecorded Unconditional Purchase Obligation, Due after Five Years	43
Long-term Contract for Purchase of Electric Power [Domain]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	4,073
Unrecorded Unconditional Purchase Obligation, Due within One Year	486
Unrecorded Unconditional Purchase Obligation, Due within Two Years	353
Unrecorded Unconditional Purchase Obligation, Due within Three Years	367
Unrecorded Unconditional Purchase Obligation, Due within Four Years	341
Unrecorded Unconditional Purchase Obligation, Due within Five Years	242
Unrecorded Unconditional Purchase Obligation, Due after Five Years	2,284
Electric Transmission [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	190
Unrecorded Unconditional Purchase Obligation, Due within One Year	18
Unrecorded Unconditional Purchase Obligation, Due within Two Years	22
Unrecorded Unconditional Purchase Obligation, Due within Three Years	23
Unrecorded Unconditional Purchase Obligation, Due within Four Years	27
Unrecorded Unconditional Purchase Obligation, Due within Five Years	12
Unrecorded Unconditional Purchase Obligation, Due after Five Years	88
Public Utility Districts [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	89
Unrecorded Unconditional Purchase Obligation, Due within One Year	13
Unrecorded Unconditional Purchase Obligation, Due within Two Years	12
Unrecorded Unconditional Purchase Obligation, Due within Three Years	12
Unrecorded Unconditional Purchase Obligation, Due within Four Years	11
Unrecorded Unconditional Purchase Obligation, Due within Five Years	10
Unrecorded Unconditional Purchase Obligation, Due after Five Years	31
Natural gas [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	440
Unrecorded Unconditional Purchase Obligation, Due within One Year	81
Unrecorded Unconditional Purchase Obligation, Due within Two Years	44
Unrecorded Unconditional Purchase Obligation, Due within Three Years	39
Unrecorded Unconditional Purchase Obligation, Due within Four Years	38
Unrecorded Unconditional Purchase Obligation, Due within Five Years	36
Unrecorded Unconditional Purchase Obligation, Due after Five Years	202
Coal and transportationSupply Agreements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	108
Unrecorded Unconditional Purchase Obligation, Due within One Year	27
Unrecorded Unconditional Purchase Obligation, Due within Two Years	27
Unrecorded Unconditional Purchase Obligation, Due within Three Years	27
Unrecorded Unconditional Purchase Obligation, Due within Four Years	27
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	5,157
Unrecorded Unconditional Purchase Obligation, Due within One Year	771
Unrecorded Unconditional Purchase Obligation, Due within Two Years	516
Unrecorded Unconditional Purchase Obligation, Due within Three Years	475
Unrecorded Unconditional Purchase Obligation, Due within Four Years	446
Unrecorded Unconditional Purchase Obligation, Due within Five Years	301
Unrecorded Unconditional Purchase Obligation, Due after Five Years	$ 2,648

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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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).

+ 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).

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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).

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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).

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or 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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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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

No definition available.

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