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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($) | Mar. 31, 2023 | Dec. 31, 2022
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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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