Other Assets - Net Benefits Attributable to Tax Equity Investments under the Proportional Amortization Method (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Equity Method Investments and Joint Ventures [Abstract]
Income tax credits and other income tax benefits	$ 74	$ 60	$ 227	$ 184
Proportional amortization	(59)	(49)	(177)	(148)
Net benefits	$ 15	$ 11	$ 50	$ 36

Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Amount of amortization expense for investment that generates income tax credit and other income tax benefit under tax credit program accounted for using proportional amortization method.

+ References

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-Topic 740
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-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after amortization expense, of income tax credit and other income tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A

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