COMMON EQUITY (Details 2) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Numerator:
Net income (loss) from continuing operations	$ (3.9)	$ 51.7	$ 178.3	$ 150.5
Discontinued operations, net of tax	(0.8)	(2.1)	5.3	(1.2)
Preferred stock dividends of subsidiary	(0.8)	(0.8)	(1.6)	(1.6)
Noncontrolling interest in subsidiaries	0.1	0	0.1	0
Net income (loss) attributed to common shareholders	$ (5.4)	$ 48.8	$ 182.1	$ 147.7
Denominator:
Average shares of common stock - basic	79.4	78.5	79.0	78.5
Effect of dilutive securities - Stock-based compensation (in shares)	0	0.6	0.3	0.6
Effect of dilutive securities - Deferred compensation (in shares)	0	0.2	0.4	0.2
Average shares of common stock - diluted	79.4	79.3	79.7	79.3
Earnings (Loss) per common share
Basic (in dollars per share)	$ (0.07)	$ 0.62	$ 2.31	$ 1.88
Diluted (in dollars per share)	$ (0.07)	$ 0.62	$ 2.29	$ 1.86
Out-of-the-money stock options
Disclosure of antidilutive shares
Antidilutive shares excluded from calculation of diluted earnings per share		0.2	0.2	0.5