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Securities - Unrealized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value
Less than 12 Months	$ 36,503	$ 38,770
12 Months or More	1,131,136	1,195,131
Total	1,167,639	1,233,901
Unrealized Loss
Less than 12 Months	(524)	(376)
12 Months or More	(158,937)	(153,965)
Total	(159,461)	(154,341)
State and municipal securities
Fair Value
Less than 12 Months	25,235	27,106
12 Months or More	246,037	246,442
Total	271,272	273,548
Unrealized Loss
Less than 12 Months	(258)	(266)
12 Months or More	(43,357)	(41,174)
Total	(43,615)	(41,440)
Fair Value
Less than 12 Months	4,833	4,717
12 Months or More	6,123	6,131
Total	10,956	10,848
Unrealized Loss
Less than 12 Months	(328)	(447)
12 Months or More	(391)	(383)
Total	(719)	(830)
Corporate bonds
Fair Value
Less than 12 Months	800	4,254
12 Months or More	73,213	74,566
Total	74,013	78,820
Unrealized Loss
Less than 12 Months	(200)	(53)
12 Months or More	(7,970)	(8,636)
Total	(8,170)	(8,689)
U.S. treasury and government agency securities
Fair Value
Less than 12 Months	0	0
12 Months or More	58,922	77,340
Total	58,922	77,340
Unrealized Loss
Less than 12 Months	0	0
12 Months or More	(4,736)	(4,740)
Total	(4,736)	(4,740)
Commercial mortgage-backed securities
Fair Value
Less than 12 Months	0	0
12 Months or More	92,740	93,396
Total	92,740	93,396
Unrealized Loss
Less than 12 Months	0	0
12 Months or More	(11,410)	(11,063)
Total	(11,410)	(11,063)
Residential mortgage-backed securities
Fair Value
Less than 12 Months	0	60
12 Months or More	486,623	506,442
Total	486,623	506,502
Unrealized Loss
Less than 12 Months	0	(5)
12 Months or More	(66,024)	(63,115)
Total	(66,024)	(63,120)
Commercial collateralized mortgage obligations
Fair Value
Less than 12 Months	6,627	0
12 Months or More	34,799	35,183
Total	41,426	35,183
Unrealized Loss
Less than 12 Months	(64)	0
12 Months or More	(4,384)	(4,203)
Total	(4,448)	(4,203)
Residential collateralized mortgage obligations
Fair Value
Less than 12 Months	0	0
12 Months or More	126,333	130,144
Total	126,333	130,144
Unrealized Loss
Less than 12 Months	0	0
12 Months or More	(20,977)	(20,566)
Total	(20,977)	(20,566)
Asset-backed securities
Fair Value
Less than 12 Months	3,841	7,350
12 Months or More	12,469	31,618
Total	16,310	38,968
Unrealized Loss
Less than 12 Months	(2)	(52)
12 Months or More	(79)	(468)
Total	$ (81)	$ (520)

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