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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Part 3 (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax [Abstract] |  |  |  |
Reversal of reserve for lapsed statute of limitations | $ 0 | $ 73,000 |  |
Income tax penalties and interest accrued for unrecognized tax position | $ 21,000 |  |  |
Tax Rate [Abstract] |  |  |  |
Federal corporate tax rate | 21.00% | 21.00% | 21.00% | 34.00%
Federal [Member] | Minimum [Member] |  |  |  |
Income Tax [Abstract] |  |  |  |
Tax year open to examination | 2017 |  |  |
Federal [Member] | Maximum [Member] |  |  |  |
Income Tax [Abstract] |  |  |  |
Tax year open to examination | 2020 |  |  |
State [Member] | Minimum [Member] |  |  |  |
Income Tax [Abstract] |  |  |  |
Tax year open to examination | 2017 |  |  |
State [Member] | Maximum [Member] |  |  |  |
Income Tax [Abstract] |  |  |  |
Tax year open to examination | 2020 |  |  |

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