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Business Combinations - Narrative (Details) - shares |  |  | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 20, 2023 | Dec. 31, 2024
Core deposit intangible |  |  |
Business Acquisition [Line Items] |  |  |
Estimated useful life |  |  | 8 years 2 months 12 days
Signature Bridge Bank | Core deposit intangible |  |  |
Business Acquisition [Line Items] |  |  |
Estimated useful life |  | 10 years |
Signature Bridge Bank | FDIC |  |  |
Business Acquisition [Line Items] |  |  |
Shares issued (in shares) | 13,010,668 |  |
Flagstar Bancorp | Core deposit intangible |  |  |
Business Acquisition [Line Items] |  |  |
Estimated useful life |  | 10 years |

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