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Securities - Amortized Cost and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Available for sale:
Amortized Cost	$ 1,220,383		$ 1,237,433
Gross Unrealized Gains	3,564		686
Gross Unrealized Losses	(97,226)		(135,591)
Fair Value	1,126,721		1,102,528
Allowance for Credit Losses	0		0
Net Carrying Amount	1,126,721		1,102,528
Held to maturity:
Amortized Cost	11,140
Fair Value	9,742		10,456
Allowance for Credit Losses	(47)	$ (49)	(50)	$ (57)	$ (24)	$ (63)
Net Carrying Amount	11,093		11,095
Securities carried at fair value through income:
Fair Value	6,218		6,512
State and municipal securities
Available for sale:
Amortized Cost	323,137		299,642
Gross Unrealized Gains	145		216
Gross Unrealized Losses	(39,692)		(43,882)
Fair Value	283,590		255,976
Allowance for Credit Losses	0		0
Net Carrying Amount	283,590		255,976
Held to maturity:
Amortized Cost	11,140		11,145
Gross Unrealized Gains	0		0
Gross Unrealized Losses	(1,398)		(689)
Fair Value	9,742		10,456
Allowance for Credit Losses	(47)		(50)
Net Carrying Amount	11,093		11,095
Securities carried at fair value through income:
Amortized Cost	6,200		6,515
Fair Value	6,218		6,512
Net Carrying Amount	6,218		6,512
Corporate bonds
Available for sale:
Amortized Cost	80,628		83,041
Gross Unrealized Gains	520		445
Gross Unrealized Losses	(3,558)		(5,250)
Fair Value	77,590		78,236
Allowance for Credit Losses	0		0
Net Carrying Amount	77,590		78,236
U.S. treasury and government agency securities
Available for sale:
Amortized Cost	4,008		14,742
Gross Unrealized Gains	1		2
Gross Unrealized Losses	(746)		(939)
Fair Value	3,263		13,805
Allowance for Credit Losses	0		0
Net Carrying Amount	3,263		13,805
Commercial mortgage-backed securities
Available for sale:
Amortized Cost	17,111		49,943
Gross Unrealized Gains	12		0
Gross Unrealized Losses	(1,987)		(5,659)
Fair Value	15,136		44,284
Allowance for Credit Losses	0		0
Net Carrying Amount	15,136		44,284
Residential mortgage-backed securities
Available for sale:
Amortized Cost	491,604		598,380
Gross Unrealized Gains	2,242		8
Gross Unrealized Losses	(34,466)		(57,554)
Fair Value	459,380		540,834
Allowance for Credit Losses	0		0
Net Carrying Amount	459,380		540,834
Commercial collateralized mortgage obligations
Available for sale:
Amortized Cost	83,557		31,263
Gross Unrealized Gains	223		0
Gross Unrealized Losses	(1,266)		(2,697)
Fair Value	82,514		28,566
Allowance for Credit Losses	0		0
Net Carrying Amount	82,514		28,566
Residential collateralized mortgage obligations
Available for sale:
Amortized Cost	220,338		160,422
Gross Unrealized Gains	421		15
Gross Unrealized Losses	(15,511)		(19,610)
Fair Value	205,248		140,827
Allowance for Credit Losses	0		0
Net Carrying Amount	$ 205,248		$ 140,827

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