Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Available-for-sale debt securities
Total available-for-sale securities	$ 822,182	$ 769,641
Gross Unrealized Gains	680	1,161
Gross Unrealized Losses	78,962	83,901
Approximate Fair Value	743,900	686,901
Mortgage-backed - GSE residential
Available-for-sale debt securities
Total available-for-sale securities	297,941	197,243
Gross Unrealized Gains	216	232
Gross Unrealized Losses	25,224	25,166
Approximate Fair Value	272,933	172,309
Collateralized mortgage obligations - GSE residential
Available-for-sale debt securities
Total available-for-sale securities	10,256	11,629
Gross Unrealized Gains	0	0
Gross Unrealized Losses	740	743
Approximate Fair Value	9,516	10,886
State and political subdivisions
Available-for-sale debt securities
Total available-for-sale securities	504,236	551,007
Gross Unrealized Gains	464	929
Gross Unrealized Losses	51,751	57,440
Approximate Fair Value	452,949	494,496
Corporate bonds
Available-for-sale debt securities
Total available-for-sale securities	9,749	9,762
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,247	552
Approximate Fair Value	8,502	$ 9,210
Mutual funds
Equity Securities
Approximate Fair Value	$ 4,000

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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