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INVESTMENT SECURITIES, Investment Securities in a Continuous Unrealized Loss Position (Details) $ in Thousands | Sep. 30, 2020 USD ($) position | Dec. 31, 2019 USD ($) position
--- | --- | ---
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 107 | 88
12 months or longer | position | 3 | 62
Total | position | 110 | 150
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 67,768 | $ 710,602
12 months or longer | 14 | 83,378
Total | 67,782 | 793,980
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses |  |
Less than 12 months | 286 | 8,351
12 months or longer | 0 | 789
Total | $ 286 | $ 9,140
Equity and Other Securities, Continuous Unrealized Loss Position, Number of Positions |  |
Less than 12 months | position | 1 |
12 months or longer | position | 0 |
Total | position | 1 |
Equity and Other Securities, Continuous Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 81 |
12 months or longer | 0 |
Total | 81 |
Equity and Other Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 20 |
12 months or longer | 0 |
Total | 20 |
Available-for-sale, allowance for credit losses | $ 0 |
U.S. Treasury Securities [Member] |  |
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 1 | 12
12 months or longer | position | 0 | 5
Total | position | 1 | 17
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 1,010 | $ 592,678
12 months or longer | 0 | 25,998
Total | 1,010 | 618,676
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses |  |
Less than 12 months | 0 | 7,970
12 months or longer | 0 | 5
Total | $ 0 | $ 7,975
Obligations of State and Political Subdivisions [Member] |  |
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 1 | 21
12 months or longer | position | 0 | 0
Total | position | 1 | 21
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 196 | $ 22,716
12 months or longer | 0 | 0
Total | 196 | 22,716
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses |  |
Less than 12 months | 0 | 26
12 months or longer | 0 | 0
Total | $ 0 | $ 26
Government Agency Mortgage-Backed Securities [Member] |  |
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 91 | 50
12 months or longer | position | 2 | 52
Total | position | 93 | 102
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 62,318 | $ 89,237
12 months or longer | 14 | 52,975
Total | 62,332 | 142,212
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses |  |
Less than 12 months | 278 | 341
12 months or longer | 0 | 766
Total | $ 278 | $ 1,107
Government Agency Collateralized Mortgage Obligations [Member] |  |
Available-for-Sale Portfolio in Unrealized Loss Positions, Number of Positions |  |
Less than 12 months | position | 14 | 5
12 months or longer | position | 1 | 5
Total | position | 15 | 10
Available-for-Sale Securities, in Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 4,244 | $ 5,971
12 months or longer | 0 | 4,405
Total | 4,244 | 10,376
Available-for-Sale Portfolio, Debt Maturities, Gross Unrealized Losses |  |
Less than 12 months | 8 | 14
12 months or longer | 0 | 18
Total | $ 8 | $ 32
Equity Securities, at Fair Value [Member] |  |
Equity and Other Securities, Continuous Unrealized Loss Position, Number of Positions |  |
Less than 12 months | position | 1 |
12 months or longer | position | 0 |
Total | position | 1 |
Equity and Other Securities, Continuous Unrealized Loss Position, Fair Value |  |
Less than 12 months | $ 81 |
12 months or longer | 0 |
Total | 81 |
Equity and Other Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |
Less than 12 months | 20 |
12 months or longer | 0 |
Total | $ 20 |

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