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Loans and Leases and the Allowance for Credit Losses - Loan Modification Activities to Borrowers Experiencing Financial Difficulty on Financing Receivables (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modifications other than troubled debt restructuring | $ 638 | $ 304
Guaranteed by Government-Related Entities [Member] |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modifications other than troubled debt restructuring | 44 | 23
Unfunded Commitments to Extend Credit [Member] |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |
Financing receivable, modifications other than troubled debt restructuring | $ 29 | $ 11

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- Definition Financing receivable, modifications other than troubled debt restructuring. + References No definition available. + Details
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- Details
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