STOCK-BASED COMPENSATION PLANS, Unrecognized Stock-Based Compensation Expense and Stock Option Exercises (Details) - Stock Options [Member] - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unrecognized Stock-Based Compensation Expense and Stock Option Exercises [Abstract]
Unrecognized stock-based compensation expense related to non-vested stock options	$ 4.7
Weighted average period for recognition of unrecognized compensation cost	3 years 3 months 18 days
Total fair value of stock options vested	$ 2.3	$ 2.2	$ 2.1
Proceeds from stock option exercises	9.4	7.7
Related tax benefits from stock option exercises	$ 1.6	$ 2.3
Shares issued in connection with stock option exercise (in shares)	0.3	0.2
Total intrinsic value of options exercised	$ 8.4	$ 7.6	$ 10.3