DEBT (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Long-Term Debt
Principal value of long-term debt obligations	$ 1,500.0		$ 1,500.0		$ 1,500.0
Unamortized basis adjustment for terminated interest rate swaps	28.3		28.3		35.3
Unamortized bond discount	(2.9)		(2.9)		(3.4)
Long-term debt	1,525.4		1,525.4		1,531.9
Long-term debt - fair value	1,693.0		1,693.0
Interest expense	18.3	15.6	53.3	44.5
Interest income	(1.4)	(2.5)	(4.3)	(6.1)
Interest expense-net	16.9	13.1	49.0	38.4
3.50% Notes due 2014
Long-Term Debt
Stated rate (as a percent)	3.50%		3.50%		3.50%
Principal value of long-term debt obligations	500.0		500.0		500.0
4.90% Notes due 2019
Long-Term Debt
Stated rate (as a percent)	4.90%		4.90%		4.90%
Principal value of long-term debt obligations	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%
Principal value of long-term debt obligations	$ 300.0		$ 300.0		$ 300.0