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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 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | $ 215,380 | $ 208,165
Gross Unrealized Gain | 1,215 | 330
Gross Unrealized Loss | 20,400 | 19,568
Estimated Fair Value | 196,195 | 188,927
Held to maturity: |  |
Amortized Cost | 404,208 | 509,008
Gross Unrealized Gains | 923 | 658
Gross Unrealized Losses | 30,608 | 34,598
Estimated Fair Value | 374,523 | 475,068
U.S. government agencies |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 9,292 | 9,141
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | 1,066 | 1,259
Estimated Fair Value | 8,226 | 7,882
Treasury securities |  |
Held to maturity: |  |
Amortized Cost | 69,432 | 133,735
Gross Unrealized Losses | 1,038 | 2,921
Estimated Fair Value | 68,394 | 130,814
Corporate bonds |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 29,882 | 29,964
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | 3,077 | 2,177
Estimated Fair Value | 26,805 | 27,787
Municipal securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 2,322 | 10,324
Gross Unrealized Gain | 182 | 326
Gross Unrealized Loss | 0 | 8
Estimated Fair Value | 2,504 | 10,642
Held to maturity: |  |
Amortized Cost | 168,175 | 191,680
Gross Unrealized Gains | 923 | 658
Gross Unrealized Losses | 6,123 | 8,285
Estimated Fair Value | 162,975 | 184,053
Mortgage-backed securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 164,419 | 145,896
Gross Unrealized Gain | 1,014 | 1
Gross Unrealized Loss | 15,621 | 15,556
Estimated Fair Value | 149,812 | 130,341
Held to maturity: |  |
Amortized Cost | 119,872 | 132,693
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 15,105 | 14,708
Estimated Fair Value | 104,767 | 117,985
Collateralized mortgage obligations |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 18,757 | 21,981
Gross Unrealized Gain | 19 | 3
Gross Unrealized Loss | 1,702 | 1,827
Estimated Fair Value | 17,074 | 20,157
Held to maturity: |  |
Amortized Cost | 37,437 | 41,759
Gross Unrealized Losses | 7,276 | 7,425
Estimated Fair Value | $ 30,161 | $ 34,334

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