EARNINGS PER COMMON SHARE - Additional Information (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Series A Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from computation of diluted earnings per share	1,648,318
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from computation of diluted earnings per share	818,093	830,755	846,808
Shares excluded from computation of diluted earnings per share, exercise price, lower range limit (in dollars per share)	$ 117.09	$ 105.12	$ 94.76
Shares excluded from computation of diluted earnings per share, exercise price, upper range limit (in dollars per share)	$ 141.56	$ 132.95	$ 119.19