SHORT-TERM DEBT AND LINES OF CREDIT (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Short-term borrowings
Short-term borrowings	$ 303.7		$ 95.4
Commercial paper
Short-term borrowings
Short-term borrowings	103.7		95.4
Average discount rate (as a percent)	0.21%		0.24%
Average amount of short-term borrowings	57.8	186.5
Loan under term credit facility
Short-term borrowings
Short-term borrowings	200.0
Average interest rate (as a percent)	0.80%
Average amount of short-term borrowings	$ 8.9