STOCK (Details) (USD $) In Millions, except Per Share data, unless otherwise specified			9 Months Ended		1 Months Ended	9 Months Ended		31 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Common Stock	Sep. 30, 2011 Common Stock	Mar. 31, 2010 Treasury Stock	Sep. 30, 2012 Treasury Stock	Sep. 30, 2011 Treasury Stock	Sep. 30, 2012 Treasury Stock
Changes in common shares and treasury stock
Common stock issued, balance at beginning of period	206.0	205.1	205.1	204.8
Treasury stock balance at beginning of period						1.4	0.1
Stock-based compensation			0.9	0.1		0.2	0
Treasury stock purchases						1.2	1.2
Common stock issued, balance at end of period	206.0	205.1	206.0	204.9
Treasury stock balance at end of period						2.8	1.3	2.8
Balance, beginning of period (in dollars )	$ 198.0	$ 89.7				$ 89.7	$ 3.2
Stock-based compensation (in dollars )						15.0	0
Treasury stock purchases (in dollars )						93.3	81.6
Balance, end of period (in dollars )	198.0	89.7				198.0	84.8	198.0
Shares authorized to be repurchased (in dollars)					300.0
Shares repurchased, shares								2.5
Shares repurchased, average cost per share								$ 70.31
Remaining repurchased available under the authorization (in dollars)						$ 125.1