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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, 2024 | Dec. 31, 2023
--- | --- | ---
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | $ 288,167 | $ 215,380
Gross Unrealized Gains | 3,338 | 1,215
Gross Unrealized Losses | 13,938 | 20,400
Estimated Fair Value | 277,567 | 196,195
Held to maturity: |  |
Amortized Cost | 341,911 | 404,208
Gross Unrealized Gains | 578 | 923
Gross Unrealized Losses | 23,176 | 30,608
Estimated Fair Value | 319,313 | 374,523
Treasury security |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 14,968 |
Gross Unrealized Gains | 3 |
Gross Unrealized Losses | 4 |
Estimated Fair Value | 14,967 |
U.S. government agencies |  |
Held to maturity: |  |
Amortized Cost | 9,410 | 9,292
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 736 | 1,066
Estimated Fair Value | 8,674 | 8,226
Corporate bonds |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 27,823 | 29,882
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 1,823 | 3,077
Estimated Fair Value | 26,000 | 26,805
Municipal securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 2,319 | 2,322
Gross Unrealized Gains | 122 | 182
Gross Unrealized Losses | 0 | 0
Estimated Fair Value | 2,441 | 2,504
Held to maturity: |  |
Amortized Cost | 156,506 | 168,175
Gross Unrealized Gains | 578 | 923
Gross Unrealized Losses | 5,538 | 6,123
Estimated Fair Value | 151,546 | 162,975
Mortgage-backed securities |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 227,136 | 164,419
Gross Unrealized Gains | 3,202 | 1,014
Gross Unrealized Losses | 10,904 | 15,621
Estimated Fair Value | 219,434 | 149,812
Held to maturity: |  |
Amortized Cost | 111,767 | 119,872
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 10,945 | 15,105
Estimated Fair Value | 100,822 | 104,767
Collateralized mortgage obligations |  |
Available for sale: |  |
Available-for-sale debt securities, amortized cost basis | 15,921 | 18,757
Gross Unrealized Gains | 11 | 19
Gross Unrealized Losses | 1,207 | 1,702
Estimated Fair Value | 14,725 | 17,074
Held to maturity: |  |
Amortized Cost | 34,460 | 37,437
Gross Unrealized Losses | 5,694 | 7,276
Estimated Fair Value | 28,766 | 30,161
Treasury securities |  |
Held to maturity: |  |
Amortized Cost | 29,768 | 69,432
Gross Unrealized Losses | 263 | 1,038
Estimated Fair Value | $ 29,505 | $ 68,394

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