GENERAL AND SIGNIFICANT ACCOUNTING POLICIES - COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 2015
Changes in accumulated other comprehensive loss by component, net of taxes
Balance		$ 450.6			$ 450.6
Net gain (loss) in prior service cost					0.7	$ (0.2)
Amortization of prior service cost	$ (0.2)		$ (0.2)		(0.6)	(0.6)
Amortization of net loss	1.0		0.9		2.1	2.3
Foreign currency translation adjustment			0.6		(0.1)	0.7
Balance	434.4				434.4
Pensions
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	(41.3)	(41.7)	(44.6)	$ (45.0)	(41.7)	(45.0)
Net gain (loss) in prior service cost				(0.2)
Amortization of prior service cost	(0.3)	(0.4)	(0.2)	(0.4)
Amortization of net loss	0.8	0.8	0.9	1.0
Balance	(40.8)	(41.3)	(43.9)	(44.6)	(40.8)	(43.9)
Post Retirement
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	(3.8)	(4.7)	(6.8)	(7.2)	(4.7)	(7.2)
Net gain (loss) in prior service cost		0.7
Amortization of prior service cost			0.1
Amortization of net loss	0.2	0.2	0.2	0.4
Balance	(3.6)	(3.8)	(6.5)	(6.8)	(3.6)	(6.5)
Non-Qualified Plans
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	(0.8)	(0.9)	(0.7)	(0.7)	(0.9)	(0.7)
Amortization of prior service cost	0.1		(0.1)
Amortization of net loss		0.1	(0.2)
Balance	(0.7)	(0.8)	(1.0)	(0.7)	(0.7)	(1.0)
Foreign Currency Transaction
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	0.9	1.0	0.4	0.3	1.0	0.3
Foreign currency translation adjustment		(0.1)	0.6	0.1
Balance	0.9	0.9	1.0	0.4	0.9	1.0
Interest Hedge
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	(0.6)	(0.6)	(0.7)	(0.7)	(0.6)	(0.7)
Balance	(0.6)	(0.6)	(0.7)	(0.7)	(0.6)	(0.7)
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive loss by component, net of taxes
Balance	(45.6)	(46.9)	(52.4)	(53.3)	(46.9)	(53.3)
Net gain (loss) in prior service cost		0.7		(0.2)
Amortization of prior service cost	(0.2)	(0.4)	(0.2)	(0.4)
Amortization of net loss	1.0	1.1	0.9	1.4
Foreign currency translation adjustment		(0.1)	0.6	0.1
Balance	$ (44.8)	$ (45.6)	$ (51.1)	$ (52.4)	$ (44.8)	$ (51.1)