STOCK BASED AND DEFERRED COMPENSATION - Summary of Additional Information Regarding Stock Plan (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
|||
| Summary of stock based compensation agreements | ||||
| Unrecognized stock-based compensation cost | $ 22,742 | $ 18,439 | ||
| Weighted average years expense recognition period | 2 years 5 months 16 days | 2 years 5 months 23 days | ||
| Total stock-based awards outstanding (in shares) | [1] | 1,308,289 | 1,269,657 | |
| ||||
| X | ||||||||||
- Definition Share based compensation arrangement by share based payment award number of shares outstanding. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
|