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EMPLOYEE STOCK COMPENSATION - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
	Aug. 21, 2012	Mar. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	May 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested options outstanding (in shares)			0		0
Restricted stock awards and units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 7.0
Expense recognition period			2 years 1 month 6 days
Restricted stock awards and units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			1 year
Restricted stock awards and units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			5 years
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Award expiration period			7 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			5 years
Award expiration period			10 years
Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period	10 years
Common stock issued upon exercise of SARs (in shares)		305,772
Tax benefit recognized in connection with exercise of SARs		$ 2.1
Share-based compensation arrangement by share-based payment award, non-option equity instruments, outstanding, number (in shares)			0	0	1,559,012
2018 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for grant (in shares)						4,417,882
Common stock available under new plan (in shares)			3,221,555