Variable Interest Entities - Investments in Qualified Affordable Housing Tax Credits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Affordable Housing Investments
Variable Interest Entity [Line Items]
Impairment losses	$ 0	$ 0	$ 0
Applicable income tax expense
Variable Interest Entity [Line Items]
Proportional amortization	163	150	140
Tax credits and other benefits	$ (193)	$ (175)	$ (163)

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

+ References

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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