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SECURITIES - Held to Maturity Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Amortized Cost, Held to maturity: |  |
Within one year | $ 1,885 |
One to five years | 23,140 |
Five to ten years | 11,535 |
Beyond ten years | 49,140 |
Total | 85,700 | $ 133,638
Estimated Fair Value, Held to maturity: |  |
Within one year | 1,902 |
One to five years | 24,452 |
Five to ten years | 12,144 |
Beyond ten years | 50,827 |
Estimated Fair Value | 89,325 | 135,027
State and municipal obligations |  |
Amortized Cost, Held to maturity: |  |
Total | 23,715 | 41,008
Estimated Fair Value, Held to maturity: |  |
Estimated Fair Value | 25,121 | 41,817
U.S. GSE residential mortgage-backed securities |  |
Amortized Cost, Held to maturity: |  |
Total | 6,272 | 8,142
Estimated Fair Value, Held to maturity: |  |
Estimated Fair Value | 6,499 | 8,093
U.S. GSE residential collateralized mortgage obligations |  |
Amortized Cost, Held to maturity: |  |
Total | 18,511 | 39,936
Estimated Fair Value, Held to maturity: |  |
Estimated Fair Value | 18,991 | 40,498
U.S. GSE commercial mortgage-backed securities |  |
Amortized Cost, Held to maturity: |  |
Total | 13,069 | 17,215
Estimated Fair Value, Held to maturity: |  |
Estimated Fair Value | 13,694 | 17,235
U.S. GSE commercial collateralized mortgage obligations |  |
Amortized Cost, Held to maturity: |  |
Total | 24,133 | 27,337
Estimated Fair Value, Held to maturity: |  |
Estimated Fair Value | $ 25,020 | $ 27,384

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