DEBT - SUMMARY (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Debt
Capital leases	$ 1.1	$ 2.6
Total Debt	839.3	738.9
Less current portion	(29.2)	(31.8)
Total Long-term Debt	810.1	707.1
5.79%, payable through 2020
Debt
Total Debt	$ 21.0	$ 24.5
Interest rate (as a percent)	5.79%	5.79%
3.66%, payable through 2023
Debt
Total Debt	$ 54.7	$ 59.3
Interest rate (as a percent)	3.66%	3.66%
4.16%, payable through 2027
Debt
Total Debt	$ 52.4	$ 55.0
Interest rate (as a percent)	4.16%	4.16%
3.37 %, payable through 2027
Debt
Total Debt	$ 75.0	$ 75.0
Interest rate (as a percent)	3.37%	3.37%
3.14%, payable through 2031
Debt
Total Debt	$ 200.0	$ 200.0
Interest rate (as a percent)	3.14%	3.14%
4.31%, payable through 2032
Debt
Total Debt	$ 36.3	$ 37.5
Interest rate (as a percent)	4.31%	4.31%
4.35%, payable through 2044
Debt
Total Debt	$ 100.0	$ 100.0
Interest rate (as a percent)	4.35%	4.35%
3.92%, payable through 2045
Debt
Total Debt	$ 73.2	$ 75.0
Interest rate (as a percent)	3.92%	3.92%
5.34%, payable through 2028
Debt
Total Debt	$ 24.2	$ 26.4
Interest rate (as a percent)	5.34%	5.34%
5.27%, payable through 2029
Debt
Total Debt	$ 26.4	$ 28.6
Interest rate (as a percent)	5.27%	5.27%
Revolving Credit Facility
Debt
Total Debt	$ 175.0	$ 55.0