STOCK-BASED COMPENSATION PLANS - Activity in Long-Term Incentive Program (Details) - Stock Options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Options, Outstanding [Roll Forward]
Outstanding, beginning of period (in shares)	1,502,994	1,644,361
Granted (in shares)	254,496	199,110
Exercised (in shares)	(197,564)	(331,315)
Forfeited (in shares)	(17,667)	(9,162)
Outstanding, end of period (in shares)	1,542,259	1,502,994
Exercisable, end of period (in shares)	978,833
Weighted-average exercise price of shares [Abstract]
Outstanding, beginning of period (in dollars per share)	$ 42.82	$ 38.36
Granted (in dollars per share)	51.68	59.41
Exercised (in dollars per share)	32.65	30.42
Forfeited (in dollars per share)	50.97	51.29
Outstanding, end of period (in dollars per share)	45.49	$ 42.82
Exercisable, end of period (in dollars per share)	$ 40.77