STOCK-BASED COMPENSATION PLANS - Summary of Fully Vested and Exercisable Stock Options and Stock Options Expected to Vest (Details) - Stock options $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Fully vested and exercisable, total shares (in shares) | shares	211
Fully vested and exercisable, weighted-average exercise price (in dollars per share) | $ / shares	$ 26.74
Fully vested and exercisable, aggregate intrinsic value | $	$ 0
Fully vested and exercisable, weighted-average remaining contractual term (in years)	3 years 9 months 18 days
Expected to vest, total shares (in shares) | shares	223
Expected to vest, weighted-average exercise price (in dollars per share) | $ / shares	$ 25.95
Expected to vest, aggregate intrinsic value | $	$ 0
Expected to vest, weighted-average remaining contractual term (in years)	4 years