SHARE-BASED AWARDS AND OPTIONS - Stock Options Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Share-based compensation expense | $ 16,496 | $ 15,205 | $ 27,914 | $ 30,104 |
Employee stock option | ||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Share-based compensation expense | 900 | 1,600 | 1,500 | |
Aggregate intrinsic value of stock options exercised | 18,900 | $ 4,600 | ||
Total unrecognized compensation cost | $ 6,000 | $ 6,000 | ||
Weighted-average period of unrecognized compensation cost | 2 years 2 months 12 days | |||
Weighted average grant date fair value for each option granted (USD per share) | $ 39.60 | $ 35.09 | $ 39.60 | $ 35.09 |