Outstanding Loans and Leases and Allowance for Credit Losses - Allowance for Credit Losses (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||||
|---|---|---|---|---|---|---|
Dec. 31, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
Sep. 30, 2024 |
Sep. 30, 2025 |
Sep. 30, 2024 |
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| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||
| Allowance for credit losses, period increase (decrease) | $ (73) | $ 25 | ||||
| Provision for credit losses | 1,328 | $ 1,547 | 4,354 | $ 4,479 | ||
| Net charge-offs | (1,367) | $ (1,534) | (4,344) | $ (4,565) | ||
| Decrease in net charge-offs | $ 167 | $ 221 | ||||
| Scenario, Forecast | ||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||
| Unemployment rate, current economic outlook (just below) | 5.00% | 5.00% | ||||
| U.S. gross domestic product, current economic outlook (as a percent) | 1.40% | 0.70% | ||||
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- Definition Allowance For Credit Losses, United States Gross Domestic Product, Current Economic Outlook No definition available.
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- Definition Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery), Period Increase (Decrease) No definition available.
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- Definition Financing Receivable, Excluding Accrued Interest, And Off-Balance Sheet, Credit Loss, Allowance, Increase (Decrease) No definition available.
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- Definition Unemployment Rate, Current Economic Outlook No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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