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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Mar. 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 | $ 958,560,000 | $ 972,207,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 958,560,000 | 972,207,000
Held-to-maturity, gross unrealized gains | 503,000 | 70,000
Held-to-maturity, gross unrealized losses | (108,938,000) | (127,038,000)
Held to maturity, fair value | 850,125,000 | 845,239,000
Accrued interest | 2,600,000 | 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 | 322,691,000 | 331,281,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 322,691,000 | 331,281,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (45,007,000) | (50,147,000)
Held to maturity, fair value | 277,684,000 | 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 | 233,796,000 | 235,971,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 233,796,000 | 235,971,000
Held-to-maturity, gross unrealized gains | 139,000 | 59,000
Held-to-maturity, gross unrealized losses | (24,973,000) | (29,503,000)
Held to maturity, fair value | 208,962,000 | 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 | 109,694,000 | 111,904,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 109,694,000 | 111,904,000
Held-to-maturity, gross unrealized gains | 176,000 | 0
Held-to-maturity, gross unrealized losses | (3,729,000) | (5,419,000)
Held to maturity, fair value | 106,141,000 | 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 | 52,120,000 | 52,356,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 52,120,000 | 52,356,000
Held-to-maturity, gross unrealized gains | 164,000 | 11,000
Held-to-maturity, gross unrealized losses | (3,020,000) | (3,076,000)
Held to maturity, fair value | 49,264,000 | 49,291,000
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 1,977,000 | 2,372,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 1,977,000 | 2,372,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (99,000) | (133,000)
Held to maturity, fair value | 1,878,000 | 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 | 145,898,000 | 145,823,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 145,898,000 | 145,823,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (22,149,000) | (26,467,000)
Held to maturity, fair value | 123,749,000 | 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 | 62,384,000 | 62,500,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 62,384,000 | 62,500,000
Held-to-maturity, gross unrealized gains | 24,000 | 0
Held-to-maturity, gross unrealized losses | (8,728,000) | (10,741,000)
Held to maturity, fair value | 53,680,000 | 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 | (1,233,000) | (1,552,000)
Held to maturity, fair value | $ 28,767,000 | $ 28,448,000

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