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Loans and Leases and the Allowance for Credit Losses - Changes in Allowance for Credit Losses (Detail) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Beginning balance | $ 2,129 | $ 1,925
Provision for credit losses | 200 | 120
Net charge-offs |  |
Charge-offs | (163) | (95)
Recoveries | 25 | 25
Net charge-offs | (138) | (70)
Ending balance | 2,191 | 1,975
Commercial and Industrial [Member] |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Beginning balance | 620 | 568
Provision for credit losses | 137 | 21
Net charge-offs |  |
Charge-offs | (78) | (20)
Recoveries | 5 | 10
Net charge-offs | (73) | (10)
Ending balance | 684 | 579
Commercial Real Estate [Member] |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Beginning balance | 764 | 611
Provision for credit losses | 9 | 86
Net charge-offs |  |
Charge-offs | (25) | (29)
Recoveries | 6 | 1
Net charge-offs | (19) | (28)
Ending balance | 754 | 669
Residential [Member] |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Beginning balance | 116 | 115
Provision for credit losses | 2 | (1)
Net charge-offs |  |
Charge-offs | (1) | (2)
Recoveries | 1 | 1
Net charge-offs |  | (1)
Ending balance | 118 | 113
Consumer [Member] |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Beginning balance | 629 | 631
Provision for credit losses | 52 | 14
Net charge-offs |  |
Charge-offs | (59) | (44)
Recoveries | 13 | 13
Net charge-offs | (46) | (31)
Ending balance | $ 635 | $ 614

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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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph c -Publisher SEC + Details
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