Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Available-for-sale debt securities
Total available-for-sale securities	$ 764,749	$ 716,952
Gross Unrealized Gains	312	31,568
Gross Unrealized Losses	108,534	2,551
Approximate Fair Value	656,527	745,969
Mortgage-backed - GSE residential
Available-for-sale debt securities
Total available-for-sale securities	178,287	161,675
Gross Unrealized Gains	0	1,809
Gross Unrealized Losses	27,761	1,774
Approximate Fair Value	150,526	161,710
Collateralized mortgage obligations - GSE residential
Available-for-sale debt securities
Total available-for-sale securities	12,489	18,130
Gross Unrealized Gains	0	311
Gross Unrealized Losses	752	10
Approximate Fair Value	11,737	18,431
State and political subdivisions
Available-for-sale debt securities
Total available-for-sale securities	568,863	532,906
Gross Unrealized Gains	299	29,329
Gross Unrealized Losses	79,696	767
Approximate Fair Value	489,466	561,468
Corporate bonds
Available-for-sale debt securities
Total available-for-sale securities	5,110	4,241
Gross Unrealized Gains	13	119
Gross Unrealized Losses	325	0
Approximate Fair Value	4,798	$ 4,360
Mutual funds
Equity Securities
Approximate Fair Value	$ 2,000

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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