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SECURITIES - Investment Securities Available for Sale in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 396,199 | $ 88,270
12 months or longer | 6,500 | 4,606
Total | 402,699 | 92,876
Unrealized Losses |  |
Less than 12 months | 5,534 | 368
12 months or longer | 74 | 37
Total | 5,608 | 405
U.S. Treasury notes and bonds |  |
Fair Value |  |
Less than 12 months | 19,909 |
12 months or longer | 0 |
Total | 19,909 |
Unrealized Losses |  |
Less than 12 months | 30 |
12 months or longer | 0 |
Total | 30 |
Mortgage-backed securities, residential |  |
Fair Value |  |
Less than 12 months | 340,858 | 70,037
12 months or longer | 0 | 970
Total | 340,858 | 71,007
Unrealized Losses |  |
Less than 12 months | 5,216 | 200
12 months or longer | 0 | 1
Total | 5,216 | 201
Corporate bonds and notes |  |
Fair Value |  |
Less than 12 months | 3,965 | 2,988
12 months or longer | 0 | 0
Total | 3,965 | 2,988
Unrealized Losses |  |
Less than 12 months | 35 | 12
12 months or longer | 0 | 0
Total | 35 | 12
SBA loan pools |  |
Fair Value |  |
Less than 12 months | 31,467 | 15,245
12 months or longer | 6,500 | 3,636
Total | 37,967 | 18,881
Unrealized Losses |  |
Less than 12 months | 253 | 156
12 months or longer | 74 | 36
Total | $ 327 | $ 192

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