SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Stock-Based Compensation (Details) - Time Lapse Restricted Shares |
12 Months Ended |
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Dec. 31, 2017 | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Vesting increment, starting with the second anniversary, over six years | 20.00% |
| Award vesting period | 6 years |
| Award amortization period | 6 years |
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- Definition Share Based Compensation Arrangement by Share Based Payment Award, Amortization Period No definition available.
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- Definition Share Based Compensation Arrangement by Share Based Payment Award Vesting Increment, Percentage No definition available.
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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