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Loans and Leases (Narrative) (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2016 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Total loans pledged to secure borrowings |  | $ 7,300 |  | $ 7,300 |  | $ 5,200
Loans and leases, deferred fees and costs |  | 58 |  | 58 |  | 62
Discounts on acquired loans |  | 760 |  | 760 |  | 439
Principal Balance of Loan |  | 48,462 |  | 48,462 |  | 37,681
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss |  | 47,989 |  | 47,989 |  | 37,256
Proceeds from Sale of Loans Receivable |  |  |  | 43 | $ 115 |
Interest income recognized on leases |  | 6 | $ 6 | 17 | $ 16 |
Receivables Acquired with Deteriorated Credit Quality |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Principal Balance of Loan |  | 569 |  | 569 |  | 200
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss |  | 506 |  | 506 |  | 179
Asset Pledged as Collateral |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Total loans pledged to secure borrowings |  | $ 31,000 |  | $ 31,000 |  | 22,000
Minimum |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Lease term |  | 3 years |  | 3 years |  |
Maximum |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Lease term |  | 5 years |  | 5 years |  |
Loans [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Interest Receivable |  | $ 191 |  | $ 191 |  | $ 148
Multifamily Loan Securitization [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans To Others Outstanding Balance |  | $ 32 |  | $ 32 |  |
Multifamily Loan Securitization [Member] | Pacific Premier Bancorp |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Proceeds from Sale of Loans Receivable | $ 509 |  |  |  |  |

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