Variable Interest Entities - Summary of the Impact of Qualifying LIHTC Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Low income housing tax credits
Variable Interest Entity [Line Items]
Amortization of qualifying LIHTC investments	$ 12	$ 9
Low income housing tax credits and other tax benefits related to qualifying LIHTC investments	(12)	(9)
Other tax benefits related to qualifying LIHTC investments
Variable Interest Entity [Line Items]
Low income housing tax credits and other tax benefits related to qualifying LIHTC investments	$ (2)	$ (3)

Amount of affordable housing tax credits and other tax benefits recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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Amount of amortization expense of investment in qualified affordable housing projects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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