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Securities - Unrealized Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value
Less than 12 Months	$ 38,770	$ 794,894
12 Months or More	1,195,131	801,830
Total	1,233,901	1,596,724
Unrealized Loss
Less than 12 Months	(376)	(59,754)
12 Months or More	(153,965)	(144,737)
Total	(154,341)	(204,491)
State and municipal securities
Fair Value
Less than 12 Months	27,106	171,079
12 Months or More	246,442	175,011
Total	273,548	346,090
Unrealized Loss
Less than 12 Months	(266)	(14,947)
12 Months or More	(41,174)	(43,658)
Total	(41,440)	(58,605)
Fair Value
Less than 12 Months	4,717	6,518
12 Months or More	6,131	0
Total	10,848	6,518
Unrealized Loss
Less than 12 Months	(447)	(482)
12 Months or More	(383)	0
Total	(830)	(482)
Corporate bonds
Fair Value
Less than 12 Months	4,254	69,618
12 Months or More	74,566	11,640
Total	78,820	81,258
Unrealized Loss
Less than 12 Months	(53)	(5,581)
12 Months or More	(8,636)	(1,610)
Total	(8,689)	(7,191)
U.S. government and agency securities
Fair Value
Less than 12 Months	0	152,471
12 Months or More	77,340	95,576
Total	77,340	248,047
Unrealized Loss
Less than 12 Months	0	(7,373)
12 Months or More	(4,740)	(8,966)
Total	(4,740)	(16,339)
Commercial mortgage-backed securities
Fair Value
Less than 12 Months	0	37,083
12 Months or More	93,396	54,860
Total	93,396	91,943
Unrealized Loss
Less than 12 Months	0	(3,416)
12 Months or More	(11,063)	(10,177)
Total	(11,063)	(13,593)
Residential mortgage-backed securities
Fair Value
Less than 12 Months	60	231,848
12 Months or More	506,442	340,455
Total	506,502	572,303
Unrealized Loss
Less than 12 Months	(5)	(20,465)
12 Months or More	(63,115)	(56,997)
Total	(63,120)	(77,462)
Commercial collateralized mortgage obligations
Fair Value
Less than 12 Months	0	21,999
12 Months or More	35,183	16,814
Total	35,183	38,813
Unrealized Loss
Less than 12 Months	0	(2,516)
12 Months or More	(4,203)	(3,001)
Total	(4,203)	(5,517)
Residential collateralized mortgage obligations
Fair Value
Less than 12 Months	0	48,749
12 Months or More	130,144	97,621
Total	130,144	146,370
Unrealized Loss
Less than 12 Months	0	(3,928)
12 Months or More	(20,566)	(19,838)
Total	(20,566)	(23,766)
Asset-backed securities
Fair Value
Less than 12 Months	7,350	62,047
12 Months or More	31,618	9,853
Total	38,968	71,900
Unrealized Loss
Less than 12 Months	(52)	(1,528)
12 Months or More	(468)	(490)
Total	$ (520)	$ (2,018)

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