Variable Interest Entities - Schedule of Investments, Proportional Amortization Method (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Proportional amortization	$ 54,000,000	$ 50,000,000	$ 160,000,000	$ 150,000,000
Tax credits and other benefits	(71,000,000)	(67,000,000)	(199,000,000)	(190,000,000)
Changes in carrying amounts of equity method investments	2,000,000	2,000,000	6,000,000	6,000,000
Impairment losses	$ 0	$ 0	$ 0	$ 0

Investment Program, Proportional Amortization Method, Applied, Equity Method Expenses

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Amount of impairment loss for investment that generates income tax credit and other income tax benefit 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/2003/role/recommendedDisclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)
-Publisher FASB
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 323
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
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-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
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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

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
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-Section 50
-Paragraph 1A
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