RETIREMENT PLANS - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Retirement Benefits [Abstract]
Net periodic benefit costs		$ 0.6	$ 1.0	$ 1.2	$ 1.9
Service cost component		0.8	$ 0.9	1.7	$ 1.9
Estimated fair value of plan assets		33.8		33.8		$ 37.8
Defer payment and taxation, base salary, percentage (up to)	75.00%
Defer payment and taxation, bonus and other eligible cash compensation, percentage (up to)	100.00%
Deferred compensation plan, fair value of assets		$ 3.2		$ 3.2		$ 2.0