EMPLOYEE BENEFITS - Summary of RSU and Share Transactions (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Stock Units (RSUs)
Units
Beginning balance (in shares)	674,218
Granted (in shares)	165,930
Shares issued (in shares)	(223,484)
Forfeited (in shares)	(22,041)
Ending balance (in shares)	594,623	674,218
Weighted Average Grant-Date Fair Value
Beginning balance (in dollars per share)	$ 63.42
Granted (in dollars per share)	81.89	$ 88.23	$ 67.91
Shares issued (in dollars per share)	69.03
Forfeited (in dollars per share)	83.86
Ending balance (in dollars per share)	$ 65.70	$ 63.42
Performance Shares
Units
Beginning balance (in shares)	447,805
Granted (in shares)	286,645
Shares issued (in shares)	(256,914)
Forfeited (in shares)	(13,029)
Ending balance (in shares)	464,507	447,805
Weighted Average Grant-Date Fair Value
Beginning balance (in dollars per share)	$ 69.93
Granted (in dollars per share)	76.08	$ 75.36	$ 68.33
Shares issued (in dollars per share)	56.88
Forfeited (in dollars per share)	84.28
Ending balance (in dollars per share)	$ 80.54	$ 69.93