DEBT (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Long-Term Debt
Line of credit, current	$ 322.0		$ 322.0		$ 0.0
Debt instrument, face amount	1,822.0		1,822.0		1,500.0
Unamortized basis adjustment for terminated interest rate swaps	7.4		7.4		8.8
Unamortized bond discount	(3.8)		(3.8)		(4.0)
Fair-value interest rate swaps	13.7		13.7		(0.9)
Long-term debt	1,839.3		1,839.3		$ 1,503.9
Interest expense	16.8	$ 20.6	49.7	$ 53.2
Interest income	(2.0)	(2.3)	(7.2)	(7.2)
Interest expense-net	$ 14.8	$ 18.3	$ 42.5	$ 46.0
4.90% Notes due 2019
Long-Term Debt
Fixed Rate Received	4.90%		4.90%		4.90%
Debt instrument, face amount	$ 700.0		$ 700.0		$ 700.0
5.90% Notes due 2039
Long-Term Debt
Fixed Rate Received	5.90%		5.90%		5.90%
Debt instrument, face amount	$ 300.0		$ 300.0		$ 300.0
4.60% Notes due 2044
Long-Term Debt
Fixed Rate Received	4.60%		4.60%		4.60%
Debt instrument, face amount	$ 500.0		$ 500.0		$ 500.0