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Business Combinations and Asset Acquisitions - acquisition-related expenses (Details) - Bank of Commerce - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | $ 568 | $ 2,192 | $ 4,904 | $ 2,702
Compensation and employee benefits |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | 205 | 0 | 1,144 | 0
Occupancy |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | 8 | 0 | 928 | 0
Data processing and software |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | 219 | 1 | 1,640 | 1
Legal and professional fees |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | 133 | 2,153 | 378 | 2,663
Advertising and promotion |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | 0 | 0 | 18 | 0
Other noninterest expenses |  |  |  |
Asset Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs | $ 3 | $ 38 | $ 796 | $ 38

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