SHORT-TERM DEBT AND LINES OF CREDIT (Details 2) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Short-term borrowings
Total short-term credit capacity	$ 450.0	$ 250.0
Short-term debt	347.2	95.4
Available capacity under existing agreements	102.8	154.6
Revolving credit facility maturing on May 17, 2014
Short-term borrowings
Total short-term credit capacity	135.0	135.0
Revolving credit facility maturing on June 13, 2017
Short-term borrowings
Total short-term credit capacity	115.0	115.0
Commercial paper
Short-term borrowings
Short-term debt	147.2	95.4
Loan under term credit facility
Short-term borrowings
Total short-term credit capacity	200.0
Short-term debt	$ 200.0