Securities - Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Amortized cost and fair value of securities available for sale
Amortized Cost	$ 878,445	$ 1,062,649
Gross Unrealized Gains	1,301	424
Gross Unrealized Losses	(114,902)	(139,794)
Fair Value	764,844	923,279
Obligations of states and political subdivisions
Amortized cost and fair value of securities available for sale
Amortized Cost	20,310	36,374
Gross Unrealized Gains	130	119
Gross Unrealized Losses	(1,878)	(1,883)
Fair Value	18,562	34,610
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	114,637	72,383
Gross Unrealized Gains	605	109
Gross Unrealized Losses	(2,676)	(4,458)
Fair Value	112,566	68,034
Government agency mortgage backed securities \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	191,650	301,400
Gross Unrealized Gains	374	172
Gross Unrealized Losses	(19,177)	(24,968)
Fair Value	172,847	276,604
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	6,010	6,029
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(466)	(637)
Fair Value	5,544	5,392
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	408,364	485,164
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(71,481)	(85,883)
Fair Value	336,883	399,281
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	137,474	161,299
Gross Unrealized Gains	192	24
Gross Unrealized Losses	(19,224)	(21,965)
Fair Value	$ 118,442	$ 139,358

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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