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BASIS OF PRESENTATION AND ACCOUNTING POLICIES, Recently Adopted Accounting Standard (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018
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Recently Adopted Accounting Standards [Abstract] |  |  |
Right-of-use assets | $ 17,885 |  | $ 0
Lease liabilities | 18,359 |  |
Accumulated Other Comprehensive Income [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | (463)
ASU 2016-02 [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Right-of-use assets | 20,700 |  |
Lease liabilities | 21,000 |  |
ASU 2018-02 [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  |  | 0
ASU 2018-02 [Member] | Retained Earnings [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  | $ 463 | $ 463
ASU 2018-02 [Member] | Accumulated Other Comprehensive Income [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income | $ (463) | $ (463) |

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