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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Recently Adopted and New Accounting Pronouncements (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Recently Adopted Accounting Pronouncements [Abstract] |  |  |
Total assets | $ 11,410,295 | $ 10,607,295 | $ 10,746,198
Total liabilities | 9,555,061 | 8,893,512 |
ASU 2016-02 [Member] | Cumulative Effect Adjustment [Member] |  |  |
Recently Adopted Accounting Pronouncements [Abstract] |  |  |
Total assets |  | 34,200 |
Total liabilities |  | $ 34,200 |
ASU 2016-13 [Member] | Cumulative Effect Adjustment [Member] |  |  |
New Accounting Pronouncements [Abstract] |  |  |
Increase in retained earnings | 500 |  |
Decrease in allowance for loan losses | (700) |  |
Adjustment to loans | 1,000 |  |
Increase in other liabilities | $ 1,200 |  |

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