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Business Combinations and Asset Acquisitions - acquisition-related expenses (Details) - Bank of Commerce - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	$ 2,587	$ 0
Compensation and employee benefits
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	370	0
Occupancy
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	819	0
Data processing and software
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	1,039	0
Legal and professional fees
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	92	0
Advertising and promotion
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	18	0
Other noninterest expenses
Asset Acquisition [Line Items]
Business Combination, Acquisition Related Costs	$ 249	$ 0

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460

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