PENSION AND OTHER POST-EMPLOYMENT BENEFIT PLANS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Changes in net periodic benefit cost
Defined benefit plan, contributions by employer			$ 1.9	$ 2.5
Pension Benefits
Changes in net periodic benefit cost
Defined Benefit Plan, Net Periodic Benefit Cost Excluding Settlements, Curtailments and Actuarial Gains (Losses)	$ (0.6)	$ 1.0	(1.0)	2.0
Service cost – benefits earned during the period	0.7	0.7	1.4	1.5
Interest cost on projected benefit obligations	2.8	3.7	5.8	7.4
Expected return on plan assets	(4.1)	(3.4)	(8.2)	(6.9)
Net actuarial (gains)/losses	13.1	(1.5)	19.2	(1.5)
Total net periodic expense/(benefit)	12.5	(0.5)	18.2	0.5
Other Benefits
Changes in net periodic benefit cost
Defined Benefit Plan, Net Periodic Benefit Cost Excluding Settlements, Curtailments and Actuarial Gains (Losses)	0.7	0.8	1.4	1.6
Service cost – benefits earned during the period	0.2	0.3	0.5	0.6
Interest cost on projected benefit obligations	0.5	0.5	0.9	1.0
Expected return on plan assets	0.0	0.0	0.0	0.0
Net actuarial (gains)/losses	0.0	0.0	0.0	0.0
Total net periodic expense/(benefit)	$ 0.7	$ 0.8	$ 1.4	$ 1.6