Securities - Amortized Cost, Fair Value and Weighted Average Yield by Maturity Date (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost
Within one year	$ 1,076	$ 741
After one to five years	6,478	4,938
After five to ten years	121,832	90,436
After ten years	640,255	620,837
Amortized Cost	769,641	716,952
Estimated fair value
Within one year	1,077	746
After one to five years	6,634	5,221
After five to ten years	120,528	97,050
After ten years	558,662	642,952
Total	$ 686,901	$ 745,969
Weighted average yield
Within one year	3.54%	3.49%
After one to five years	4.62%	4.35%
After five to ten years	3.28%	3.32%
After ten years	2.60%	2.37%
Total	2.74%	2.50%
Mortgage-backed - GSE residential
Amortized cost
Within one year	$ 0	$ 0
After one to five years	18	30
After five to ten years	105	148
After ten years	197,120	161,497
Amortized Cost	197,243	161,675
Estimated fair value
Within one year	0	0
After one to five years	17	31
After five to ten years	101	156
After ten years	172,191	161,523
Total	$ 172,309	$ 161,710
Weighted average yield
Within one year	0.00%	0.00%
After one to five years	4.77%	4.67%
After five to ten years	4.05%	4.00%
After ten years	2.39%	1.62%
Total	2.39%	1.62%
Collateralized mortgage obligations - GSE residential
Amortized cost
Within one year	$ 0	$ 0
After one to five years	0	0
After five to ten years	2,344	2,421
After ten years	9,285	15,709
Amortized Cost	11,629	18,130
Estimated fair value
Within one year	0	0
After one to five years	0	0
After five to ten years	2,229	2,559
After ten years	8,657	15,872
Total	$ 10,886	$ 18,431
Weighted average yield
Within one year	0.00%	0.00%
After one to five years	0.00%	0.00%
After five to ten years	2.77%	2.77%
After ten years	2.25%	1.61%
Total	2.36%	1.77%
State and political subdivisions
Amortized cost
Within one year	$ 1,076	$ 741
After one to five years	6,310	4,304
After five to ten years	109,771	84,230
After ten years	433,850	443,631
Amortized Cost	551,007	532,906
Estimated fair value
Within one year	1,077	746
After one to five years	6,471	4,520
After five to ten years	109,134	90,645
After ten years	377,814	465,557
Total	$ 494,496	$ 561,468
Weighted average yield
Within one year	3.54%	3.49%
After one to five years	4.60%	4.14%
After five to ten years	3.08%	3.29%
After ten years	2.70%	2.67%
Total	2.80%	2.78%
Corporate bonds
Amortized cost
Within one year	$ 0	$ 0
After one to five years	150	604
After five to ten years	9,612	3,637
After ten years	0	0
Amortized Cost	9,762	4,241
Estimated fair value
Within one year	0	0
After one to five years	146	670
After five to ten years	9,064	3,690
After ten years	0	0
Total	$ 9,210	$ 4,360
Weighted average yield
Within one year	0.00%	0.00%
After one to five years	5.43%	5.83%
After five to ten years	5.70%	4.28%
After ten years	0.00%	0.00%
Total	5.70%	4.50%