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Securities - Amortized Cost and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Available for sale:
Amortized Cost	$ 1,321,942	$ 1,407,675
Gross Unrealized Gains	533	297
Gross Unrealized Losses	(162,427)	(154,341)
Fair Value	1,160,048	1,253,631
Allowance for Credit Losses	0	0
Net Carrying Amount	1,160,048	1,253,631
Held to maturity:
Amortized Cost	11,673
Fair Value	10,876	10,848
Allowance for Credit Losses	(57)	(63)	$ (935)	$ (899)
Net Carrying Amount	11,616	11,615
Securities carried at fair value through income:
Fair Value	6,499	6,808
State and municipal securities
Available for sale:
Amortized Cost	320,357	323,356
Gross Unrealized Gains	159	210
Gross Unrealized Losses	(46,106)	(41,440)
Fair Value	274,410	282,126
Allowance for Credit Losses	0	0
Net Carrying Amount	274,410	282,126
Held to maturity:
Amortized Cost	11,673	11,678
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(797)	(830)
Fair Value	10,876	10,848
Allowance for Credit Losses	(57)	(63)
Net Carrying Amount	11,616	11,615
Securities carried at fair value through income:
Amortized Cost	6,515	6,815
Fair Value	6,499	6,808
Net Carrying Amount	6,499	6,808
Corporate bonds
Available for sale:
Amortized Cost	102,794	92,244
Gross Unrealized Gains	338	80
Gross Unrealized Losses	(8,510)	(8,689)
Fair Value	94,622	83,635
Allowance for Credit Losses	0	0
Net Carrying Amount	94,622	83,635
U.S. treasury and government agency securities
Available for sale:
Amortized Cost	49,110	84,377
Gross Unrealized Gains	7	3
Gross Unrealized Losses	(4,564)	(4,740)
Fair Value	44,553	79,640
Allowance for Credit Losses	0	0
Net Carrying Amount	44,553	79,640
Commercial mortgage-backed securities
Available for sale:
Amortized Cost	103,845	104,459
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(10,950)	(11,063)
Fair Value	92,895	93,396
Allowance for Credit Losses	0	0
Net Carrying Amount	92,895	93,396
Residential mortgage-backed securities
Available for sale:
Amortized Cost	534,062	569,622
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(66,436)	(63,120)
Fair Value	467,626	506,502
Allowance for Credit Losses	0	0
Net Carrying Amount	467,626	506,502
Commercial collateralized mortgage obligations
Available for sale:
Amortized Cost	49,077	39,386
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(4,442)	(4,203)
Fair Value	44,635	35,183
Allowance for Credit Losses	0	0
Net Carrying Amount	44,635	35,183
Residential collateralized mortgage obligations
Available for sale:
Amortized Cost	143,438	150,710
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(21,382)	(20,566)
Fair Value	122,056	130,144
Allowance for Credit Losses	0	0
Net Carrying Amount	122,056	130,144
Asset-backed securities
Available for sale:
Amortized Cost	19,259	43,521
Gross Unrealized Gains	29	4
Gross Unrealized Losses	(37)	(520)
Fair Value	19,251	43,005
Allowance for Credit Losses	0	0
Net Carrying Amount	$ 19,251	$ 43,005

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