Loans and Allowance for Credit Losses - Past due aging analysis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Past due aging analysis of loans
Loans	$ 2,606,430	$ 2,443,994
Nonaccrual	9,007	3,794
30 - 89 Days Past Due
Past due aging analysis of loans
Loans	3,753	4,963
Current
Past due aging analysis of loans
Loans	2,593,670	2,435,237
Commercial
Past due aging analysis of loans
Loans	1,705,143	1,563,356
Nonaccrual	7,571	3,074
Commercial | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	2,929	2,794
Commercial | Current
Past due aging analysis of loans
Loans	1,694,643	1,557,488
Commercial | Commercial and industrial
Past due aging analysis of loans
Loans	582,387	583,876
Nonaccrual	6,560	1,162
Commercial | Commercial and industrial | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	2,929	2,426
Commercial | Commercial and industrial | Current
Past due aging analysis of loans
Loans	572,898	580,288
Commercial | Real estate construction
Past due aging analysis of loans
Loans	97,742	97,810
Nonaccrual	115	440
Commercial | Real estate construction | Current
Past due aging analysis of loans
Loans	97,627	97,370
Commercial | Commercial real estate
Past due aging analysis of loans
Loans	1,025,014	881,670
Nonaccrual	896	1,472
Commercial | Commercial real estate | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans		368
Commercial | Commercial real estate | Current
Past due aging analysis of loans
Loans	1,024,118	879,830
Consumer
Past due aging analysis of loans
Loans	901,287	880,638
Nonaccrual	1,436	720
Consumer | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	824	2,169
Consumer | Current
Past due aging analysis of loans
Loans	899,027	877,749
Consumer | Residential | Real estate first mortgage
Past due aging analysis of loans
Loans	717,793	679,551
Nonaccrual	886	535
Consumer | Residential | Real estate first mortgage | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	108	1,545
Consumer | Residential | Real estate first mortgage | Current
Past due aging analysis of loans
Loans	716,799	677,471
Consumer | Residential | Real estate junior lien
Past due aging analysis of loans
Loans	152,677	150,479
Nonaccrual	546	184
Consumer | Residential | Real estate junior lien | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	538	377
Consumer | Residential | Real estate junior lien | Current
Past due aging analysis of loans
Loans	151,593	149,918
Consumer | Other revolving and installment
Past due aging analysis of loans
Loans	30,817	50,608
Nonaccrual	4	1
Consumer | Other revolving and installment | 30 - 89 Days Past Due
Past due aging analysis of loans
Loans	178	247
Consumer | Other revolving and installment | Current
Past due aging analysis of loans
Loans	$ 30,635	$ 50,360