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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
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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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