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SECURITIES - Available for Sale Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Available for sale: |  |
Less than 12 months, Estimated Fair Value | $ 95,818 | $ 175,474
Less than 12 months, Gross Unrealized Losses | (614) | (778)
Greater than 12 months, Estimated Fair Value | 33,120 | 214,908
Greater than 12 months, Gross Unrealized Losses | (1,788) | (4,619)
U.S. Treasury securities |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value |  | 50,822
Less than 12 months, Gross Unrealized Losses |  | (11)
U.S. GSE securities |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value |  | 0
Less than 12 months, Gross Unrealized Losses |  | 0
Greater than 12 months, Estimated Fair Value |  | 4,995
Greater than 12 months, Gross Unrealized Losses |  | (5)
State and municipal obligations |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value | 5,310 | 4,982
Less than 12 months, Gross Unrealized Losses | (10) | (42)
Greater than 12 months, Estimated Fair Value |  | 76
Greater than 12 months, Gross Unrealized Losses |  | (1)
U.S. GSE residential mortgage-backed securities |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value |  | 2,935
Less than 12 months, Gross Unrealized Losses |  | (30)
Greater than 12 months, Estimated Fair Value | 152 | 39,617
Greater than 12 months, Gross Unrealized Losses | (6) | (438)
U.S. GSE residential collateralized mortgage obligations |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value | 55,832 | 81,377
Less than 12 months, Gross Unrealized Losses | (226) | (480)
Greater than 12 months, Estimated Fair Value |  | 93,403
Greater than 12 months, Gross Unrealized Losses |  | (984)
U.S. GSE commercial mortgage-backed securities |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value | 14,994 | 6,648
Less than 12 months, Gross Unrealized Losses | (253) | (70)
Greater than 12 months, Estimated Fair Value |  | 0
Greater than 12 months, Gross Unrealized Losses |  | 0
U.S. GSE commercial collateralized mortgage obligations |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value | 11,755 | 28,710
Less than 12 months, Gross Unrealized Losses | (52) | (145)
Greater than 12 months, Estimated Fair Value |  | 9,614
Greater than 12 months, Gross Unrealized Losses |  | (144)
Other asset backed securities |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value |  | 0
Less than 12 months, Gross Unrealized Losses |  | 0
Greater than 12 months, Estimated Fair Value | 3,450 | 23,401
Greater than 12 months, Gross Unrealized Losses | (300) | (849)
Corporate |  |
Available for sale: |  |
Less than 12 months, Estimated Fair Value | 7,927 | 0
Less than 12 months, Gross Unrealized Losses | (73) | 0
Greater than 12 months, Estimated Fair Value | 29,518 | 43,802
Greater than 12 months, Gross Unrealized Losses | $ (1,482) | $ (2,198)

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