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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Dec. 31, 2023 | Dec. 31, 2022
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | $ 925,198,000 | $ 972,207,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 925,198,000 | 972,207,000
Held-to-maturity, gross unrealized gains | 75,000 | 70,000
Held-to-maturity, gross unrealized losses | (110,443,000) | (127,038,000)
Held to maturity, fair value | 814,830,000 | 845,239,000
Accrued interest | 3,600,000 | 3,700,000
MBS pass-through securities issued by FHLMC, FNMA and GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 306,261,000 | 331,281,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 306,261,000 | 331,281,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (44,396,000) | (50,147,000)
Held to maturity, fair value | 261,865,000 | 281,134,000
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 226,416,000 | 235,971,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 226,416,000 | 235,971,000
Held-to-maturity, gross unrealized gains | 28,000 | 59,000
Held-to-maturity, gross unrealized losses | (24,869,000) | (29,503,000)
Held to maturity, fair value | 201,575,000 | 206,527,000
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 101,502,000 | 111,904,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 101,502,000 | 111,904,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (4,779,000) | (5,419,000)
Held to maturity, fair value | 96,723,000 | 106,485,000
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 51,006,000 | 52,356,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 51,006,000 | 52,356,000
Held-to-maturity, gross unrealized gains | 0 | 11,000
Held-to-maturity, gross unrealized losses | (5,235,000) | (3,076,000)
Held to maturity, fair value | 45,771,000 | 49,291,000
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 1,853,000 | 2,372,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 1,853,000 | 2,372,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (90,000) | (133,000)
Held to maturity, fair value | 1,763,000 | 2,239,000
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 146,126,000 | 145,823,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 146,126,000 | 145,823,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (21,994,000) | (26,467,000)
Held to maturity, fair value | 124,132,000 | 119,356,000
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 62,034,000 | 62,500,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 62,034,000 | 62,500,000
Held-to-maturity, gross unrealized gains | 47,000 | 0
Held-to-maturity, gross unrealized losses | (7,884,000) | (10,741,000)
Held to maturity, fair value | 54,197,000 | 51,759,000
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 30,000,000 | 30,000,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 30,000,000 | 30,000,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (1,196,000) | (1,552,000)
Held to maturity, fair value | $ 28,804,000 | $ 28,448,000

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