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Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,058,471	$ 1,051,313
Gross Unrealized Gains	468	1,746
Gross Unrealized Losses	(85,100)	(83,751)
Fair Value	973,839	969,308
Interest receivable	3,800	3,800
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	123,296	144,292
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(9,847)	(10,506)
Fair Value	113,449	133,786
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,310	33,342
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(524)	(829)
Fair Value	24,786	32,513
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	569,806	507,942
Gross Unrealized Gains	342	1,068
Gross Unrealized Losses	(50,823)	(48,071)
Fair Value	519,325	460,939
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	42,301	44,707
Gross Unrealized Gains	2	7
Gross Unrealized Losses	(7,005)	(6,537)
Fair Value	35,298	38,177
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	272,741	290,775
Gross Unrealized Gains	124	458
Gross Unrealized Losses	(16,325)	(17,808)
Fair Value	256,540	273,425
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,017	30,255
Gross Unrealized Gains	0	213
Gross Unrealized Losses	(576)	0
Fair Value	$ 24,441	$ 30,468

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