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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | $ 931,587,000 | $ 342,222,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 931,587,000 | 342,222,000
Held-to-maturity, gross unrealized gains | 1,048,000 | 3,400,000
Held-to-maturity, gross unrealized losses | (85,249,000) | (2,867,000)
Held to maturity, fair value | 847,386,000 | 342,755,000
Accrued interest | 3,100,000 | 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 | 337,998,000 | 126,990,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 337,998,000 | 126,990,000
Held-to-maturity, gross unrealized gains | 4,000 | 2,110,000
Held-to-maturity, gross unrealized losses | (34,731,000) | (712,000)
Held to maturity, fair value | 303,271,000 | 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 | 230,553,000 | 106,851,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 230,553,000 | 106,851,000
Held-to-maturity, gross unrealized gains | 172,000 | 668,000
Held-to-maturity, gross unrealized losses | (20,766,000) | (1,045,000)
Held to maturity, fair value | 209,959,000 | 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 | 118,956,000 | 4,866,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 118,956,000 | 4,866,000
Held-to-maturity, gross unrealized gains | 853,000 | 128,000
Held-to-maturity, gross unrealized losses | (2,574,000) | 0
Held to maturity, fair value | 117,235,000 | 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 | 12,329,000 |
Allowance for Credit Losses | 0 |
Net Carrying Amount | 12,329,000 |
Held-to-maturity, gross unrealized gains | 0 |
Held-to-maturity, gross unrealized losses | (982,000) |
Held to maturity, fair value | 11,347,000 |
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 3,244,000 | 4,840,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 3,244,000 | 4,840,000
Held-to-maturity, gross unrealized gains | 0 | 198,000
Held-to-maturity, gross unrealized losses | (66,000) | 0
Held to maturity, fair value | 3,178,000 | 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 | 135,678,000 | 51,472,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 135,678,000 | 51,472,000
Held-to-maturity, gross unrealized gains | 0 | 0
Held-to-maturity, gross unrealized losses | (17,457,000) | (901,000)
Held to maturity, fair value | 118,221,000 | 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 | 62,829,000 | 47,203,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 62,829,000 | 47,203,000
Held-to-maturity, gross unrealized gains | 19,000 | 296,000
Held-to-maturity, gross unrealized losses | (8,304,000) | (209,000)
Held to maturity, fair value | 54,544,000 | 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 | (369,000) |
Held to maturity, fair value | $ 29,631,000 |

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