Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,051,313	$ 1,104,105
Gross Unrealized Gains	1,746	261
Gross Unrealized Losses	(83,751)	(102,582)
Fair Value	969,308	1,001,784
Interest receivable	3,800	3,700
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	144,292	145,416
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(10,506)	(13,721)
Fair Value	133,786	131,695
Obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	33,342	43,479
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(829)	(1,668)
Fair Value	32,513	41,811
Collateralized mortgage obligations of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	507,942	482,039
Gross Unrealized Gains	1,068	203
Gross Unrealized Losses	(48,071)	(53,835)
Fair Value	460,939	428,407
Residential mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	44,707	49,418
Gross Unrealized Gains	7	3
Gross Unrealized Losses	(6,537)	(7,834)
Fair Value	38,177	41,587
Commercial mortgage-backed securities of U.S. government corporations and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	290,775	352,465
Gross Unrealized Gains	458	0
Gross Unrealized Losses	(17,808)	(25,152)
Fair Value	273,425	327,313
Corporate obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	0	500
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30,255	30,788
Gross Unrealized Gains	213	55
Gross Unrealized Losses	0	(372)
Fair Value	$ 30,468	$ 30,471

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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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