Fair value - Carrying amounts and estimated fair value of the company's (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financial assets
Investment securities available for sale, at fair value	$ 131,623	$ 94,699
Loans held for sale	7,900	5,100
Fair Value, Inputs, Level 1 [Member] | Reported Value Measurement [Member]
Financial assets
Cash	22,176	12,071
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Financial assets
Cash	22,176	12,071
Fair Value, Inputs, Level 2 [Member] | Reported Value Measurement [Member]
Financial assets
Cash equivalents	32,720	80,545
Investment securities available for sale, at fair value	130,123	92,949
Federal Home Loan Bank stock	373	353
Loans held for sale	7,963	5,141
Bank owned life insurance	12,638	12,494
Accrued interest receivable	3,321	3,245
Interest rate lock commitments	406	471
Financial liabilities
Deposits	674,641	664,048
Trust preferred securities	8,764	8,764
Other borrowings	5,676	5,660
Accrued interest payable	61	68
Forward sales commitment	556	651
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Financial assets
Cash equivalents	32,720	80,545
Investment securities available for sale, at fair value	130,123	92,949
Federal Home Loan Bank stock	373	353
Loans held for sale	7,963	5,141
Bank owned life insurance	12,638	12,494
Accrued interest receivable	3,321	3,245
Interest rate lock commitments	406	471
Financial liabilities
Deposits	674,397	663,898
Trust preferred securities	8,930	9,554
Other borrowings	5,676	5,660
Accrued interest payable	61	68
Forward sales commitment	556	651
Fair Value, Inputs, Level 3 [Member] | Reported Value Measurement [Member]
Financial assets
Investment securities available for sale, at fair value	1,500	1,750
Loans	527,556	526,457
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Financial assets
Investment securities available for sale, at fair value	1,500	1,750
Loans	$ 515,482	$ 526,668