Investment Securities - Schedule of Investment Income (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Investments, Debt and Equity Securities [Abstract] | ||||
| Taxable interest | $ 221 | $ 228 | $ 435 | $ 438 |
| Taxable dividends | 4 | 5 | 8 | 10 |
| Interest and dividends exempt from U.S. federal income tax | 6 | 6 | 11 | 12 |
| Interest and dividends on investment securities | $ 231 | $ 239 | $ 454 | $ 460 |
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- Definition Amount of operating dividend income on securities subject to state, federal and other income tax. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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