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Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,038,627	$ 1,058,154
Gross Unrealized Gains	7,257	990
Gross Unrealized Losses	(46,054)	(72,729)
Fair Value	999,830	986,415
Interest receivable	3,300	3,700
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96,544	97,045
Gross Unrealized Gains	103	0
Gross Unrealized Losses	(2,385)	(4,277)
Fair Value	94,262	92,768
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	15,260
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(189)
Fair Value	0	15,071
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	665,945	643,690
Gross Unrealized Gains	4,756	872
Gross Unrealized Losses	(33,165)	(48,278)
Fair Value	637,536	596,284
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	36,950	40,109
Gross Unrealized Gains	7	3
Gross Unrealized Losses	(5,101)	(6,905)
Fair Value	31,856	33,207
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	234,259	237,270
Gross Unrealized Gains	2,377	115
Gross Unrealized Losses	(5,403)	(12,587)
Fair Value	231,233	224,798
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,929	24,780
Gross Unrealized Gains	14	0
Gross Unrealized Losses	0	(493)
Fair Value	$ 4,943	$ 24,287

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