DEBT - SUMMARY (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt
Total debt	$ 698.9	$ 760.1
Less: Current portion	(59.2)	(59.2)
Total Long-term Debt	639.7	700.9
Less: Deferred loan fees	(15.4)	(15.3)
Total Long-term Debt, net of deferred loan fees	624.3	685.6
3.66%, payable through 2023
Debt
Total debt	$ 22.8	22.8
Interest rate (as a percent)	3.66%
4.16%, payable through 2027
Debt
Total debt	$ 34.0	34.0
Interest rate (as a percent)	4.16%
3.37 %, payable through 2027
Debt
Total debt	$ 75.0	75.0
Interest rate (as a percent)	3.37%
3.14%, payable through 2031
Debt
Total debt	$ 160.4	169.6
Interest rate (as a percent)	3.14%
4.31%, payable through 2032
Debt
Total debt	$ 27.9	27.9
Interest rate (as a percent)	4.31%
5.34%, payable through 2028
Debt
Total debt	$ 16.5	17.6
Interest rate (as a percent)	5.34%
5.27%, payable through 2029
Debt
Total debt	$ 18.7	19.8
Interest rate (as a percent)	5.27%
1.22 %, payable through 2043
Debt
Total debt	$ 182.0	182.0
Interest rate (as a percent)	1.22%
1.35 %, payable through 2044
Debt
Total debt	$ 136.6	139.6
Interest rate (as a percent)	1.35%
Revolving Credit Facility
Debt
Total debt	$ 25.0	$ 71.8