Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,064,347	$ 1,058,154
Gross Unrealized Gains	3,372	990
Gross Unrealized Losses	(57,769)	(72,729)
Fair Value	1,009,950	986,415
Interest receivable	3,400	3,700
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	96,881	97,045
Gross Unrealized Gains	55	0
Gross Unrealized Losses	(3,331)	(4,277)
Fair Value	93,605	92,768
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,239	15,260
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(112)	(189)
Fair Value	10,127	15,071
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	686,862	643,690
Gross Unrealized Gains	2,389	872
Gross Unrealized Losses	(40,433)	(48,278)
Fair Value	648,818	596,284
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	39,156	40,109
Gross Unrealized Gains	5	3
Gross Unrealized Losses	(6,018)	(6,905)
Fair Value	33,143	33,207
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	226,228	237,270
Gross Unrealized Gains	923	115
Gross Unrealized Losses	(7,866)	(12,587)
Fair Value	219,285	224,798
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,981	24,780
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(9)	(493)
Fair Value	$ 4,972	$ 24,287

Interest Receivable, Debt Securities Available For Sale

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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