Securities - Amortized Cost and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Available for sale:
Amortized Cost	$ 1,276,431	$ 1,237,433
Gross Unrealized Gains	2,255	686
Gross Unrealized Losses	(117,318)	(135,591)
Fair Value	1,161,368	1,102,528
Allowance for Credit Losses	0	0
Net Carrying Amount	1,161,368	1,102,528
Held to maturity:
Amortized Cost	11,143
Fair Value	10,361	10,456
Allowance for Credit Losses	(49)	(50)	$ (24)	$ (63)
Net Carrying Amount	11,094	11,095
Securities carried at fair value through income:
Fair Value	6,512	6,512
State and municipal securities
Available for sale:
Amortized Cost	297,968	299,642
Gross Unrealized Gains	145	216
Gross Unrealized Losses	(41,142)	(43,882)
Fair Value	256,971	255,976
Allowance for Credit Losses	0	0
Net Carrying Amount	256,971	255,976
Held to maturity:
Amortized Cost	11,143	11,145
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(782)	(689)
Fair Value	10,361	10,456
Allowance for Credit Losses	(49)	(50)
Net Carrying Amount	11,094	11,095
Securities carried at fair value through income:
Amortized Cost	6,515	6,515
Fair Value	6,512	6,512
Net Carrying Amount	6,512	6,512
Corporate bonds
Available for sale:
Amortized Cost	80,252	83,041
Gross Unrealized Gains	717	445
Gross Unrealized Losses	(4,053)	(5,250)
Fair Value	76,916	78,236
Allowance for Credit Losses	0	0
Net Carrying Amount	76,916	78,236
U.S. treasury and government agency securities
Available for sale:
Amortized Cost	14,091	14,742
Gross Unrealized Gains	2	2
Gross Unrealized Losses	(811)	(939)
Fair Value	13,282	13,805
Allowance for Credit Losses	0	0
Net Carrying Amount	13,282	13,805
Commercial mortgage-backed securities
Available for sale:
Amortized Cost	86,737	49,943
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(4,888)	(5,659)
Fair Value	81,852	44,284
Allowance for Credit Losses	0	0
Net Carrying Amount	81,852	44,284
Residential mortgage-backed securities
Available for sale:
Amortized Cost	594,963	598,380
Gross Unrealized Gains	1,166	8
Gross Unrealized Losses	(47,143)	(57,554)
Fair Value	548,986	540,834
Allowance for Credit Losses	0	0
Net Carrying Amount	548,986	540,834
Commercial collateralized mortgage obligations
Available for sale:
Amortized Cost	36,077	31,263
Gross Unrealized Gains	105	0
Gross Unrealized Losses	(2,181)	(2,697)
Fair Value	34,001	28,566
Allowance for Credit Losses	0	0
Net Carrying Amount	34,001	28,566
Residential collateralized mortgage obligations
Available for sale:
Amortized Cost	166,343	160,422
Gross Unrealized Gains	117	15
Gross Unrealized Losses	(17,100)	(19,610)
Fair Value	149,360	140,827
Allowance for Credit Losses	0	0
Net Carrying Amount	$ 149,360	$ 140,827

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