Junior subordinated debentures (Details) - Junior subordinated debentures - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	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

Face (par) amount of debt instrument at time of issuance.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant