Credit Quality and the Allowance for Loan and Lease Losses - Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
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|---|---|---|---|---|---|---|---|---|
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Individually evaluated | $ 161 | $ 193 | ||||||
| Collectively evaluated | 2,761 | 2,060 | ||||||
| Total ALLL | 2,922 | [1] | 2,253 | [1] | $ 2,384 | $ 2,352 | ||
| Individually evaluated | 741 | 615 | ||||||
| Collectively evaluated | 175,404 | 121,930 | ||||||
| Total portfolio loans and leases | 176,145 | 122,545 | ||||||
| Leveraged leases | 238 | 243 | ||||||
| Commercial Leveraged Leases | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Total ALLL | 2 | 2 | ||||||
| Commercial | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Individually evaluated | 147 | 178 | ||||||
| Collectively evaluated | 1,673 | 1,008 | ||||||
| Total ALLL | 1,820 | 1,186 | 1,241 | 1,154 | ||||
| Individually evaluated | 492 | 367 | ||||||
| Collectively evaluated | 122,367 | 73,195 | ||||||
| Total portfolio loans and leases | 122,859 | 73,562 | ||||||
| Residential Mortgage | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Individually evaluated | 0 | 0 | ||||||
| Collectively evaluated | 108 | 109 | ||||||
| Total ALLL | 108 | 109 | 139 | 146 | ||||
| Individually evaluated | 143 | 143 | ||||||
| Collectively evaluated | 19,259 | 17,403 | ||||||
| Total portfolio loans and leases | 19,402 | 17,546 | ||||||
| Residential mortgage loans | 105 | 106 | 109 | |||||
| Consumer | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Individually evaluated | 14 | 15 | ||||||
| Collectively evaluated | 980 | 943 | ||||||
| Total ALLL | 994 | 958 | $ 1,004 | $ 1,052 | ||||
| Individually evaluated | 106 | 105 | ||||||
| Collectively evaluated | 33,778 | 31,332 | ||||||
| Total portfolio loans and leases | $ 33,884 | $ 31,437 | ||||||
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