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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	$ 892,605,000	$ 1,169,520,000
Available-for-sale, gross unrealized gains	34,000	11,074,000
Available-for-sale, gross unrealized losses	(90,543,000)	(13,026,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	$ 802,096,000	$ 1,167,568,000
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	$ 3,200,000	$ 3,700,000
MBS pass-through securities issued by FHLMC, FNMA and GNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	109,736,000	316,090,000
Available-for-sale, gross unrealized gains	3,000	1,224,000
Available-for-sale, gross unrealized losses	(12,133,000)	(2,784,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	97,606,000	314,530,000
CMOs issued by FHLMC
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	347,437,000	343,047,000
Available-for-sale, gross unrealized gains	0	3,209,000
Available-for-sale, gross unrealized losses	(33,682,000)	(4,829,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	313,755,000	341,427,000
CMOs issued by FNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	36,172,000	48,187,000
Available-for-sale, gross unrealized gains	0	152,000
Available-for-sale, gross unrealized losses	(3,852,000)	(611,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	32,320,000	47,728,000
CMOs issued by GNMA
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	35,120,000	56,345,000
Available-for-sale, gross unrealized gains	0	99,000
Available-for-sale, gross unrealized losses	(3,296,000)	(553,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	31,824,000	55,891,000
SBA-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	47,724,000	32,640,000
Available-for-sale, gross unrealized gains	2,000	993,000
Available-for-sale, gross unrealized losses	(3,371,000)	(155,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	44,355,000	33,478,000
Debentures of government sponsored agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	149,114,000	191,449,000
Available-for-sale, gross unrealized gains	0	25,000
Available-for-sale, gross unrealized losses	(14,008,000)	(2,947,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	135,106,000	188,527,000
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	11,904,000	11,886,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(1,635,000)	(256,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	10,269,000	11,630,000
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	116,855,000	129,009,000
Available-for-sale, gross unrealized gains	29,000	5,372,000
Available-for-sale, gross unrealized losses	(14,761,000)	(381,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	102,123,000	134,000,000
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	36,990,000	39,001,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(3,714,000)	(506,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	33,276,000	38,495,000
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, amortized cost	1,553,000	1,866,000
Available-for-sale, gross unrealized gains	0	0
Available-for-sale, gross unrealized losses	(91,000)	(4,000)
Allowance for Credit Losses	0	0
Available-for-sale securities	$ 1,462,000	$ 1,862,000

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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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