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v3.23.3

Business Combinations - Narrative (Details) $ in Millions |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Mar. 31, 2023 shares | Mar. 20, 2023 USD ($) branch | Sep. 30, 2023 USD ($) branch | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) branch | Sep. 30, 2022 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  |  | 436 |  | 436 |
Bargain purchase gain | $ |  |  | $ 0 | $ 0 | $ 2,142 | $ 0
Loans returned to the FDIC | $ |  |  |  |  | 449 |
Signature Bridge Bank |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Bargain purchase gain | $ |  | $ 2,142 |  |  | $ 2,100 |
Signature Bridge Bank | Core Deposits |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful life |  | 10 years |  |  |  |
Signature Bridge Bank | FDIC |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Shares issued (in shares) | shares | 39,032,006 |  |  |  |  |
Signature Bridge Bank | New York |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  | 29 |  |  |  |
Signature Bridge Bank | California |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  | 7 |  |  |  |
Signature Bridge Bank | North Carolina |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  | 2 |  |  |  |
Signature Bridge Bank | Connecticut |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  | 1 |  |  |  |
Signature Bridge Bank | Nevada |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of branches |  | 1 |  |  |  |

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