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SECURITIES - Investment Securities Available for Sale in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 365,276 | $ 88,270
12 months or longer | 11,470 | 4,606
Total | 376,746 | 92,876
Unrealized Losses |  |
Less than 12 months | 9,342 | 368
12 months or longer | 96 | 37
Total | 9,438 | 405
Mortgage-backed securities, residential |  |
Fair Value |  |
Less than 12 months | 339,140 | 70,037
12 months or longer | 0 | 970
Total | 339,140 | 71,007
Unrealized Losses |  |
Less than 12 months | 9,175 | 200
12 months or longer | 0 | 1
Total | 9,175 | 201
Corporate bonds and notes |  |
Fair Value |  |
Less than 12 months | 2,964 | 2,988
12 months or longer | 0 | 0
Total | 2,964 | 2,988
Unrealized Losses |  |
Less than 12 months | 36 | 12
12 months or longer | 0 | 0
Total | 36 | 12
SBA loan pools |  |
Fair Value |  |
Less than 12 months | 23,172 | 15,245
12 months or longer | 11,470 | 3,636
Total | 34,642 | 18,881
Unrealized Losses |  |
Less than 12 months | 131 | 156
12 months or longer | 96 | 36
Total | $ 227 | $ 192

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