STOCK-BASED COMPENSATION (Tables)
|9 Months Ended|
Sep. 30, 2018
|Disclosure of Compensation Related Costs, Share-based Payments [Abstract]|
|Fair Value of Employee Stock Options Granted and Determined by Black-Scholes Valuation Model Assumptions||The fair value of each option grant is estimated using the Black-Scholes option pricing model. The weighted-average assumptions used and the calculated weighted-average fair values of options granted in 2018 and 2017 are as follows:
The weighted-average assumptions used and the calculated weighted-average fair values of the RTSR portion of the LTIP awards granted in the third quarter of 2018, the second quarter of 2018 and 2017 are as follows:
Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.
Reference 1: http://www.xbrl.org/2003/role/presentationRef