DEBT - SUMMARY (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Aug. 31, 2004	Sep. 30, 2003
Debt
Capital leases	$ 2.6	$ 3.1
Total Debt	738.9	429.9
Less current portion	(31.8)	(22.0)
Total Long-term Debt	707.1	407.9
5.79%, payable through 2020
Debt
Total Debt	$ 24.5	31.5
Interest rate (as a percent)	5.79%
3.66%, payable through 2023
Debt
Total Debt	$ 59.3	68.4
Interest rate (as a percent)	3.66%
4.16%, payable through 2027
Debt
Total Debt	$ 55.0	55.0
Interest rate (as a percent)	4.16%
3.37 %, payable through 2027
Debt
Total Debt	$ 75.0
Interest rate (as a percent)	3.37%
3.14%, payable through 2031
Debt
Total Debt	$ 200.0
Interest rate (as a percent)	3.14%
4.31%, payable through 2032
Debt
Total Debt	$ 37.5	37.5
Interest rate (as a percent)	4.31%
4.35%, payable through 2044
Debt
Total Debt	$ 100.0	100.0
Interest rate (as a percent)	4.35%
3.92%, payable through 2045
Debt
Total Debt	$ 75.0	75.0
Interest rate (as a percent)	3.92%
5.34%, payable through 2028
Debt
Total Debt	$ 26.4	28.6
Interest rate (as a percent)	5.34%			5.34%
5.27%, payable through 2029
Debt
Total Debt	$ 28.6	$ 30.8
Interest rate (as a percent)	5.27%		5.27%
Revolving Credit Facility
Debt
Total Debt	$ 55.0