Loans, net and allowance for loan losses - Major Classification of Loans by Past Due Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due.
Total Due	$ 5,154	$ 3,986
Loans	2,329,173	2,730,116	$ 2,177,982
Loans > 90 Days and Accruing	13	748
Current
Financing Receivable, Recorded Investment, Past Due.
Total Due	2,324,019	2,726,130
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	2,898	2,091
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	948	367
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Total Due	1,308	1,528
Commercial
Financing Receivable, Recorded Investment, Past Due.
Total Due	414	261
Loans	613,127	599,258	679,286
Commercial | Current
Financing Receivable, Recorded Investment, Past Due.
Total Due	612,713	598,997
Commercial | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	101	137
Commercial | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	155	38
Commercial | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Total Due	158	86
Commercial real estate
Financing Receivable, Recorded Investment, Past Due.
Total Due	2,025	438
Loans	1,343,539	1,709,827	1,137,990
Increase (Decrease) in Notes Receivable	(1,200)
Commercial real estate | Current
Financing Receivable, Recorded Investment, Past Due.
Total Due	1,341,514	1,709,389
Commercial real estate | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	768	102
Commercial real estate | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	423	2
Commercial real estate | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Total Due	834	334
Residential real estate
Financing Receivable, Recorded Investment, Past Due.
Total Due	2,024	2,278
Loans	297,624	330,728	277,414
Loans > 90 Days and Accruing	13	748
Residential real estate | Current
Financing Receivable, Recorded Investment, Past Due.
Total Due	295,600	328,450
Residential real estate | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	1,552	1,162
Residential real estate | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	207	128
Residential real estate | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Total Due	265	988
Consumer
Financing Receivable, Recorded Investment, Past Due.
Total Due	691	1,009
Loans	74,883	90,303	$ 83,292
Consumer | Current
Financing Receivable, Recorded Investment, Past Due.
Total Due	74,192	89,294
Consumer | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	477	690
Consumer | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Total Due	163	199
Consumer | Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Total Due	$ 51	$ 120