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SECURITIES - Investment Securities Available for Sale in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 450,318 | $ 88,270
12 months or longer | 13,385 | 4,606
Total | 463,703 | 92,876
Unrealized Losses |  |
Less than 12 months | 8,173 | 368
12 months or longer | 225 | 37
Total | 8,398 | 405
U.S. Treasury notes and bonds |  |
Fair Value |  |
Less than 12 months | 24,819 |
12 months or longer | 0 |
Total | 24,819 |
Unrealized Losses |  |
Less than 12 months | 162 |
12 months or longer | 0 |
Total | 162 |
Mortgage-backed securities, residential |  |
Fair Value |  |
Less than 12 months | 383,380 | 70,037
12 months or longer | 4,146 | 970
Total | 387,526 | 71,007
Unrealized Losses |  |
Less than 12 months | 7,707 | 200
12 months or longer | 119 | 1
Total | 7,826 | 201
Corporate bonds and notes |  |
Fair Value |  |
Less than 12 months | 2,979 | 2,988
12 months or longer | 2,966 | 0
Total | 5,945 | 2,988
Unrealized Losses |  |
Less than 12 months | 21 | 12
12 months or longer | 34 | 0
Total | 55 | 12
SBA loan pools |  |
Fair Value |  |
Less than 12 months | 39,140 | 15,245
12 months or longer | 6,273 | 3,636
Total | 45,413 | 18,881
Unrealized Losses |  |
Less than 12 months | 283 | 156
12 months or longer | 72 | 36
Total | $ 355 | $ 192

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