DEBT (Interest Cost) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Interest Cost
Interest expense	$ 78.0	$ 80.2	$ 126.3	$ 157.1
Less: Interest capitalized	6.1	10.2	18.3	24.1
Interest cost incurred	$ 84.1	$ 90.4	144.6	$ 181.2
Decrease in interest expense			$ 30.8