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MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | $ 218,490 | $ 341,628
Gross Unrealized Gain | 44 | 3,388
Gross Unrealized Loss | 20,590 | 2,810
Estimated Fair Value | 197,944 | 342,206
Held to maturity: |  |
Amortized Cost | 633,386 | 184,263
Gross Unrealized Gains | 86 | 8,364
Gross Unrealized Losses | 37,628 | 155
Estimated Fair Value | 595,844 | 192,472
U.S. government agencies |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis |  | 10,013
Gross Unrealized Gain |  | 0
Gross Unrealized Loss |  | 42
Estimated Fair Value |  | 9,971
Held to maturity: |  |
Amortized Cost | 9,103 |
Gross Unrealized Losses | 1,277 |
Estimated Fair Value | 7,826 |
Corporate bonds |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 35,003 | 35,080
Gross Unrealized Gain |  | 940
Gross Unrealized Loss | 1,893 | 85
Estimated Fair Value | 33,110 | 35,935
Municipal securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 9,487 |
Gross Unrealized Gain | 33 |
Gross Unrealized Loss | 103 |
Estimated Fair Value | 9,417 |
Held to maturity: |  |
Amortized Cost | 192,101 | 181,310
Gross Unrealized Gains | 86 | 8,364
Gross Unrealized Losses | 10,162 | 118
Estimated Fair Value | 182,025 | 189,556
Mortgage-backed securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 150,516 | 221,610
Gross Unrealized Gain | 5 | 1,477
Gross Unrealized Loss | 16,906 | 1,779
Estimated Fair Value | 133,615 | 221,308
Held to maturity: |  |
Amortized Cost | 135,292 | 2,953
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 15,743 | 37
Estimated Fair Value | 119,549 | 2,916
Collateralized mortgage obligations |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 23,484 | 74,925
Gross Unrealized Gain | 6 | 971
Gross Unrealized Loss | 1,688 | 904
Estimated Fair Value | 21,802 | $ 74,992
Held to maturity: |  |
Amortized Cost | 43,157 |
Gross Unrealized Losses | 7,037 |
Estimated Fair Value | 36,120 |
Treasury securities |  |
Held to maturity: |  |
Amortized Cost | 253,733 |
Gross Unrealized Losses | 3,409 |
Estimated Fair Value | $ 250,324 |

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