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SECURITIES (Schedule of Carrying Value, Gross Unrealized Gains and Losses and Estimated Fair Value of Securities) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | $ 544,851 | $ 555,144
Gross Unrealized Gains | 74,982 | 48,359
Gross Unrealized Losses | (68) | 0
Held-to-maturity Securities, Fair Value | 619,765 | 603,503
U.S. government and agency securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | 2,751 | 2,813
Gross Unrealized Gains | 0 | 26
Gross Unrealized Losses | (18) | 0
Held-to-maturity Securities, Fair Value | 2,733 | 2,839
Obligations of states and political subdivisions |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | 536,767 | 545,148
Gross Unrealized Gains | 74,978 | 48,274
Gross Unrealized Losses | 0 | 0
Held-to-maturity Securities, Fair Value | 611,745 | 593,422
Commercial |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | 5,333 | 7,183
Gross Unrealized Gains | 4 | 59
Gross Unrealized Losses | (50) | 0
Held-to-maturity Securities, Fair Value | 5,287 | 7,242
Agency | Commercial |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | 5,333 | 7,183
Gross Unrealized Gains | 4 | 59
Gross Unrealized Losses | (50) | 0
Held-to-maturity Securities, Fair Value | 5,287 | 7,242
Non-agency | Commercial |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Total HTM Securities | 0 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Held-to-maturity Securities, Fair Value | $ 0 | $ 0

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