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v3.25.2

Commitments and Contingencies (Narrative) (Details) $ in Thousands | 6 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) entity | Sep. 30, 2024 | Apr. 23, 2025 USD ($)
Commitments and Contingencies Disclosure [Abstract] |  |  |  |
Financial guarantees in connection with standby letters of credit | $ 0 | $ 0 |  |
Standby letters of credit expiring within one year | 295,200 |  |  |
Standby letters of credit expiring thereafter | 26,000 |  |  |
Loss Contingency Accrual | 1,200 |  |  |
Concentration Risk [Line Items] |  |  |  |
Loss Contingency Accrual | 1,200 |  |  |
Columbia Banking Systems and Pacific Premier Bancorp Merger |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Termination Fee |  |  |  | $ 75,000
iCap Entities [Member] |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Number of Defendant Entities | entity |  | 34 |  |
Loss Contingency, Damages Sought, Value | 290,000 |  |  |
Professional Financial Investors, Inc. and Professional Investors Security Fund, Inc. [Member] |  |  |  |
Commitments and Contingencies Disclosure [Abstract] |  |  |  |
Loss Contingency Accrual | 55,000 |  |  |
Concentration Risk [Line Items] |  |  |  |
Loss Contingency Accrual | 55,000 |  |  |
Minimum | Professional Financial Investors, Inc. and Professional Investors Security Fund, Inc. [Member] |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Loss Contingency, Damages Sought, Value | 297,400 |  |  |
Maximum | Professional Financial Investors, Inc. and Professional Investors Security Fund, Inc. [Member] |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Loss Contingency, Damages Sought, Value | $ 368,100 |  |  |
Product Concentration Risk | Revenue Benchmark | Real Estate Loans As Part Of Loan Portfolio |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk (as a percent) | 75.00% |  | 75.00% |
Product Concentration Risk | Revenue Benchmark | Multifamily Loans as Part of Loan portfolio [Member] |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk (as a percent) | 19.00% |  | 19.00% |
Product Concentration Risk | Revenue Benchmark | Commercial Office Loans as Part of Loan portfolio [Member] |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk (as a percent) | 8.00% |  | 8.00% |

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