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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Sep. 30, 2022 | Dec. 31, 2021
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | $ 959,867,000 | $ 342,222,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 959,867,000 | 342,222,000
Held-to-maturity, gross unrealized gains | 0 | 3,400,000
Held-to-maturity, gross unrealized losses | (130,819,000) | (2,867,000)
Held to maturity, fair value | 829,048,000 | 342,755,000
Accrued interest | 2,600,000 | 1,100,000
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 | 335,959,000 | 126,990,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 335,959,000 | 126,990,000
Held-to-maturity, gross unrealized gains | 0 | 2,110,000
Held-to-maturity, gross unrealized losses | (53,659,000) | (712,000)
Held to maturity, fair value | 282,300,000 | 128,388,000
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 236,061,000 | 106,851,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 236,061,000 | 106,851,000
Held-to-maturity, gross unrealized gains | 0 | 668,000
Held-to-maturity, gross unrealized losses | (30,272,000) | (1,045,000)
Held to maturity, fair value | 205,789,000 | 106,474,000
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 115,043,000 | 4,866,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 115,043,000 | 4,866,000
Held-to-maturity, gross unrealized gains | 0 | 128,000
Held-to-maturity, gross unrealized losses | (6,066,000) | 0
Held to maturity, fair value | 108,977,000 | 4,994,000
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 32,070,000 |
Allowance for Credit Losses | 0 |
Net Carrying Amount | 32,070,000 |
Held-to-maturity, gross unrealized gains | 0 |
Held-to-maturity, gross unrealized losses | (2,204,000) |
Held to maturity, fair value | 29,866,000 |
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 2,373,000 | 4,840,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 2,373,000 | 4,840,000
Held-to-maturity, gross unrealized gains | 0 | 198,000
Held-to-maturity, gross unrealized losses | (143,000) | 0
Held to maturity, fair value | 2,230,000 | 5,038,000
Debentures of government- sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 145,747,000 | 51,472,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 145,747,000 | 51,472,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (25,193,000) | (901,000)
Held to maturity, fair value | 120,554,000 | 50,571,000
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 62,614,000 | 47,203,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 62,614,000 | 47,203,000
Held-to-maturity, gross unrealized gains | 0 | 296,000
Held-to-maturity, gross unrealized losses | (11,697,000) | (209,000)
Held to maturity, fair value | 50,917,000 | 47,290,000
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 30,000,000 | $ 0
Allowance for Credit Losses | 0 |
Net Carrying Amount | 30,000,000 |
Held-to-maturity, gross unrealized gains | 0 |
Held-to-maturity, gross unrealized losses | (1,585,000) |
Held to maturity, fair value | $ 28,415,000 |

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