Fair Value Measurements - Summary of carrying amounts and estimated fair values of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets:
Securities AFS	$ 852,331	$ 921,661
Securities HTM	652,056	648,394
Carrying Amount
Financial assets:
Cash and cash equivalents	395,923	595,292
Certificates of deposit in other banks	19,692	21,920
Securities AFS	852,331	921,661
Securities HTM	684,991	651,803
Other investments, including equity securities	54,257	44,008
Loans held for sale	9,764	6,447
Loans, net	4,633,409	4,572,164
Accrued interest receivable	15,908	15,277
Financial liabilities:
Deposits	6,231,120	6,465,916
Long-term borrowings	206,946	216,915
Accrued interest payable	2,852	3,078
Carrying Amount | MSR asset
Financial assets:
Servicing asset	13,226	12,436
Carrying Amount | LSR asset
Financial assets:
Servicing asset	17,550	20,055
Estimated Fair Value
Financial assets:
Cash and cash equivalents	395,923	595,292
Certificates of deposit in other banks	19,801	22,236
Securities AFS	852,331	921,661
Securities HTM	652,056	648,394
Other investments, including equity securities	54,257	44,008
Loans held for sale	9,886	6,616
Loans, net	4,548,241	4,606,851
Accrued interest receivable	15,908	15,277
Financial liabilities:
Deposits	6,214,808	6,463,064
Long-term borrowings	205,995	216,092
Accrued interest payable	2,852	3,078
Estimated Fair Value | MSR asset
Financial assets:
Servicing asset	16,621	15,599
Estimated Fair Value | LSR asset
Financial assets:
Servicing asset	17,550	20,055
Estimated Fair Value | Level 1
Financial assets:
Cash and cash equivalents	395,923	595,292
Certificates of deposit in other banks	0	0
Securities AFS	0	0
Securities HTM	0	0
Other investments, including equity securities	6,081	5,660
Loans held for sale	0	0
Loans, net	0	0
Accrued interest receivable	15,908	15,277
Financial liabilities:
Deposits	0	0
Long-term borrowings	0	0
Accrued interest payable	2,852	3,078
Estimated Fair Value | Level 1 | MSR asset
Financial assets:
Servicing asset	0	0
Estimated Fair Value | Level 1 | LSR asset
Financial assets:
Servicing asset	0	0
Estimated Fair Value | Level 2
Financial assets:
Cash and cash equivalents	0	0
Certificates of deposit in other banks	19,801	22,236
Securities AFS	844,341	913,596
Securities HTM	652,056	648,394
Other investments, including equity securities	39,383	32,110
Loans held for sale	9,886	6,616
Loans, net	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Long-term borrowings	15,001	25,097
Accrued interest payable	0	0
Estimated Fair Value | Level 2 | MSR asset
Financial assets:
Servicing asset	0	0
Estimated Fair Value | Level 2 | LSR asset
Financial assets:
Servicing asset	0	0
Estimated Fair Value | Level 3
Financial assets:
Cash and cash equivalents	0	0
Certificates of deposit in other banks	0	0
Securities AFS	7,990	8,065
Securities HTM	0	0
Other investments, including equity securities	8,793	6,238
Loans held for sale	0	0
Loans, net	4,548,241	4,606,851
Accrued interest receivable	0	0
Financial liabilities:
Deposits	6,214,808	6,463,064
Long-term borrowings	190,994	190,995
Accrued interest payable	0	0
Estimated Fair Value | Level 3 | MSR asset
Financial assets:
Servicing asset	16,621	15,599
Estimated Fair Value | Level 3 | LSR asset
Financial assets:
Servicing asset	$ 17,550	$ 20,055