DEBT (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Long-Term Debt
Debt Instrument, Face Amount	$ 1,500.0		$ 1,500.0		$ 1,500.0
Unamortized basis adjustment for terminated interest rate swaps	7.9		7.9		8.8
Unamortized bond discount	(3.9)		(3.9)		(4.0)
Interest Rate Fair Value Hedge Liability at Fair Value	2.2		2.2		(0.9)
Long-term debt	1,506.2		1,506.2		$ 1,503.9
Long-term debt - fair value	1,581.6		1,581.6
Interest expense	16.5	$ 17.8	32.9	$ 32.6
Interest income	(2.6)	(2.5)	(5.2)	(4.9)
Interest expense-net	$ 13.9	$ 15.3	$ 27.7	$ 27.7
4.90% Notes due 2019
Long-Term Debt
Stated rate (as a percent)	4.90%		4.90%		4.90%
Debt Instrument, Face Amount	$ 700.0		$ 700.0		$ 700.0
5.90% Notes due 2039
Long-Term Debt
Stated rate (as a percent)	5.90%		5.90%		5.90%
Debt Instrument, Face Amount	$ 300.0		$ 300.0		$ 300.0
4.60% Notes due 2044
Long-Term Debt
Stated rate (as a percent)	4.60%		4.60%		4.60%
Debt Instrument, Face Amount	$ 500.0		$ 500.0		$ 500.0