Variable Interest Entities - Investments in Qualified Affordable Housing Tax Credits (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Affordable Housing Investments
Variable Interest Entity [Line Items]
Impairment losses	$ 0	$ 0	$ 0	$ 0
Applicable income tax expense
Variable Interest Entity [Line Items]
Proportional amortization	42	43	77	87
Tax credits and other benefits	$ (50)	$ (50)	$ (91)	$ (101)

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
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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.

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