STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($) $ in Millions |
12 Months Ended | ||||
|---|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Shares issued during the period (in shares) | 72,760,969 | 72,932,222 | |||
| Time Lapse Restricted Shares | |||||
| 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 | ||||
| Shares issued during the period (in shares) | 0 | 0 | 700,000 | ||
| Common stock reserved for issuance upon exercise of stock options (in shares) | 4,300,000 | ||||
| Unrecognized compensation cost | $ 32.9 | $ 29.9 | |||
| Unrecognized compensation cost, period for recognition | 3 years 10 months 24 days | 3 years 9 months 18 days | |||
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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 Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 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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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares issued during the period as a result of a stock split. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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