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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Mar. 31, 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 | $ 790,264,000 | $ 342,222,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 790,264,000 | 342,222,000
Held-to-maturity, gross unrealized gains | 191,000 | 3,400,000
Held-to-maturity, gross unrealized losses | (45,943,000) | (2,867,000)
Held to maturity, fair value | 744,512,000 | 342,755,000
Accrued interest | 1,800,000 | 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 | 339,149,000 | 126,990,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 339,149,000 | 126,990,000
Held-to-maturity, gross unrealized gains | 148,000 | 2,110,000
Held-to-maturity, gross unrealized losses | (18,528,000) | (712,000)
Held to maturity, fair value | 320,769,000 | 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 | 187,459,000 | 106,851,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 187,459,000 | 106,851,000
Held-to-maturity, gross unrealized gains | 42,000 | 668,000
Held-to-maturity, gross unrealized losses | (11,811,000) | (1,045,000)
Held to maturity, fair value | 175,690,000 | 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 | 51,732,000 | 4,866,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 51,732,000 | 4,866,000
Held-to-maturity, gross unrealized gains | 0 | 128,000
Held-to-maturity, gross unrealized losses | (1,000,000) | 0
Held to maturity, fair value | 50,732,000 | 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 | 12,375,000 |
Allowance for Credit Losses | 0 |
Net Carrying Amount | 12,375,000 |
Held-to-maturity, gross unrealized gains | 0 |
Held-to-maturity, gross unrealized losses | (431,000) |
Held to maturity, fair value | 11,944,000 |
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 3,245,000 | 4,840,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 3,245,000 | 4,840,000
Held-to-maturity, gross unrealized gains | 0 | 198,000
Held-to-maturity, gross unrealized losses | (29,000) | 0
Held to maturity, fair value | 3,216,000 | 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 | 115,603,000 | 51,472,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 115,603,000 | 51,472,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (9,477,000) | (901,000)
Held to maturity, fair value | 106,126,000 | 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 | 50,701,000 | 47,203,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 50,701,000 | 47,203,000
Held-to-maturity, gross unrealized gains | 1,000 | 296,000
Held-to-maturity, gross unrealized losses | (4,667,000) | (209,000)
Held to maturity, fair value | 46,035,000 | 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 |  |
Net Carrying Amount | 30,000,000 |
Held-to-maturity, gross unrealized gains | 0 |
Held-to-maturity, gross unrealized losses | 0 |
Held to maturity, fair value | $ 30,000,000 |

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