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Junior subordinated debentures (Details) - Junior subordinated debentures - USD ($) $ in Millions | 12 Months Ended |
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Dec. 31, 2022 | Oct. 01, 2021
Subordinated Borrowing [Line Items] |  |
Debt Instrument, Interest Rate Terms | 158.00% |
Bank of Commerce |  |
Subordinated Borrowing [Line Items] |  |
Business Combination, Purchase Price Allocation, Junior Subordinated Debt |  | $ 10.3

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