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SECURITIES - Available for Sale Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Amortized Cost, Available for sale: |  |
Within one year | $ 4,131 |
One to five years | 58,608 |
Five to ten years | 38,415 |
Beyond ten years | 344,833 |
Total | 445,987 | $ 639,463
Estimated Fair Value, Available for sale: |  |
Within one year | 4,116 |
One to five years | 58,861 |
Five to ten years | 38,597 |
Beyond ten years | 348,786 |
Estimated Fair Value | 450,360 | 638,291
U.S. Treasury securities |  |
Amortized Cost, Available for sale: |  |
Total |  | 50,833
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value |  | 50,822
U.S. GSE securities |  |
Amortized Cost, Available for sale: |  |
Total |  | 5,000
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value |  | 4,995
State and municipal obligations |  |
Amortized Cost, Available for sale: |  |
Total | 40,448 | 34,303
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 42,088 | 34,964
U.S. GSE residential mortgage-backed securities |  |
Amortized Cost, Available for sale: |  |
Total | 111,398 | 84,550
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 113,235 | 84,691
U.S. GSE residential collateralized mortgage obligations |  |
Amortized Cost, Available for sale: |  |
Total | 127,369 | 278,149
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 128,804 | 277,851
U.S. GSE commercial mortgage-backed securities |  |
Amortized Cost, Available for sale: |  |
Total | 24,920 | 13,656
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 24,807 | 13,609
U.S. GSE commercial collateralized mortgage obligations |  |
Amortized Cost, Available for sale: |  |
Total | 61,102 | 102,722
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 62,336 | 104,156
Other asset backed securities |  |
Amortized Cost, Available for sale: |  |
Total | 24,250 | 24,250
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | 23,950 | 23,401
Corporate |  |
Amortized Cost, Available for sale: |  |
Total | 56,500 | 46,000
Estimated Fair Value, Available for sale: |  |
Estimated Fair Value | $ 55,140 | $ 43,802

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