Investment Securities (Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Interest and dividends on investment securities	$ 841	$ 600	$ 736
Excludes other earning assets
Taxable interest	765	533	654
Taxable dividends	17	27	21
Interest and dividends exempt from U.S. federal income tax	22	19	17
Interest and dividends on investment securities	$ 804	$ 579	$ 692

Amount of operating dividend income on securities subject to state, federal and other income tax.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

+ References

No definition available.

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Interest income, including any amortization and accretion (as applicable) of discounts and premiums, derived from debt securities issued by municipal governments, local taxing districts and US state government agencies.

+ References

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)

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