Goodwill and other intangible assets - Components of other intangible assets subject to amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 27,096	$ 27,096
Accumulated Amortization	16,502	14,912
Net Carrying Value	10,594	12,184
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	12,810	12,810
Accumulated Amortization	10,675	10,034
Net Carrying Value	2,135	2,776
Other customer relationship
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	14,286	14,286
Accumulated Amortization	5,827	4,878
Net Carrying Value	$ 8,459	$ 9,408