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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	$ 871,829,000	$ 892,605,000
Available-for-sale, gross unrealized gains	112,000	34,000
Available-for-sale, gross unrealized losses	(74,408,000)	(90,543,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	$ 797,533,000	$ 802,096,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest receivable and other assets	Interest receivable and other assets
Accrued interest	$ 3,100,000	$ 3,200,000
MBS pass-through securities issued by FHLMC, FNMA and GNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	106,151,000	109,736,000
Available-for-sale, gross unrealized gains	4,000	3,000
Available-for-sale, gross unrealized losses	(10,423,000)	(12,133,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	95,732,000	97,606,000
CMOs issued by FHLMC
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	340,647,000	347,437,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(27,514,000)	(33,682,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	313,133,000	313,755,000
CMOs issued by FNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	34,782,000	36,172,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(3,182,000)	(3,852,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	31,600,000	32,320,000
CMOs issued by GNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	33,714,000	35,120,000
Available-for-sale, gross unrealized gains	22,000	0
Available-for-sale, gross unrealized losses	(2,743,000)	(3,296,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	30,993,000	31,824,000
SBA-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	40,547,000	47,724,000
Available-for-sale, gross unrealized gains	2,000	2,000
Available-for-sale, gross unrealized losses	(2,578,000)	(3,371,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	37,971,000	44,355,000
Debentures of government- sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	149,121,000	149,114,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(12,000,000)	(14,008,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	137,121,000	135,106,000
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	11,909,000	11,904,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(1,385,000)	(1,635,000)
Allowance for Credit Losses	0
Available-for-sale securities	10,524,000	10,269,000
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	116,549,000	116,855,000
Available-for-sale, gross unrealized gains	84,000	29,000
Available-for-sale, gross unrealized losses	(11,497,000)	(14,761,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	105,136,000	102,123,000
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	36,990,000	36,990,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(3,029,000)	(3,714,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	33,961,000	33,276,000
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	1,419,000	1,553,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(57,000)	(91,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	$ 1,362,000	$ 1,462,000

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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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