CONSOLIDATED STATEMENTS OF EQUITY (USD $) In Millions, unless otherwise specified	Total	Total Common Shareholders' Equity	Deferred Compensation Trust and Treasury Stock	Common Stock	Additional Paid In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Preferred Stock of Subsidiary	Noncontrolling Interest	Total Comprehensive Income (Loss)
Balance at Dec. 31, 2008	$ 3,140.8	$ 3,089.7	$ (16.5)	$ 76.4	$ 2,487.9	$ 614.7	$ (72.8)	$ 51.1
Increase (Decrease) in Common Shareholders' Equity
Net income (loss) attributed to common shareholders	(70.6)	(69.6)				(69.6)			(1.0)	(70.6)
Other comprehensive income (loss)
Cash flow hedges (net of tax of $4.8, $4.7 and $17.0 in 2011, 2010 and 2009 respectively)	31.5	31.5					31.5			31.5
Unrecognized pension and other postretirement costs (net of tax of $5.1, $2.0 and $3.2 in 2011, 2010 and 2009 respectively)	(6.7)	(6.7)					(6.7)			(6.7)
Available-for-sale securities (net of tax of $0.1 in 2009)	(0.1)	(0.1)					(0.1)			(0.1)
Foreign currency translation (net of tax of $1.5 and $2.6 in 2010 and 2009 respectively)	4.1	4.1					4.1			4.1
Comprehensive income (loss)	(41.8)	(40.8)								(41.8)
Purchase of deferred compensation shares	(3.1)	(3.1)	(3.1)
Stock based compensation	11.4	11.4	0.1		11.3
Dividends on common stock	(206.9)	(206.9)				(206.9)
Net contributions from noncontrolling parties	0.1								0.1
Other	(0.3)	(0.3)	2.3		(1.4)	(1.2)
Balance at Dec. 31, 2009	2,900.2	2,850.0	(17.2)	76.4	2,497.8	337.0	(44.0)	51.1	(0.9)
Increase (Decrease) in Common Shareholders' Equity
Net income (loss) attributed to common shareholders	220.6	220.9				220.9			(0.3)	220.6
Other comprehensive income (loss)
Cash flow hedges (net of tax of $4.8, $4.7 and $17.0 in 2011, 2010 and 2009 respectively)	4.5	4.5					4.5			4.5
Unrecognized pension and other postretirement costs (net of tax of $5.1, $2.0 and $3.2 in 2011, 2010 and 2009 respectively)	(2.8)	(2.8)					(2.8)			(2.8)
Foreign currency translation (net of tax of $1.5 and $2.6 in 2010 and 2009 respectively)	(2.4)	(2.4)					(2.4)			(2.4)
Comprehensive income (loss)	219.9	220.2								219.9
Issuance of common stock	55.8	55.8		1.3	54.5
Purchase of deferred compensation shares	(1.2)	(1.2)	(1.2)
Stock based compensation	4.0	4.0			4.0
Dividends on common stock	(208.7)	(208.7)				(208.7)
Other	(13.0)	(14.3)	(0.1)	0.1	(15.9)	1.6			1.3
Balance at Dec. 31, 2010	2,957.0	2,905.8	(18.5)	77.8	2,540.4	350.8	(44.7)	51.1	0.1
Increase (Decrease) in Common Shareholders' Equity
Net income (loss) attributed to common shareholders	227.4	227.4				227.4			0	227.4
Other comprehensive income (loss)
Cash flow hedges (net of tax of $4.8, $4.7 and $17.0 in 2011, 2010 and 2009 respectively)	8.9	8.9					8.9			8.9
Unrecognized pension and other postretirement costs (net of tax of $5.1, $2.0 and $3.2 in 2011, 2010 and 2009 respectively)	(6.7)	(6.7)					(6.7)			(6.7)
Comprehensive income (loss)	229.6	229.6								229.6
Issuance of common stock	22.2	22.2		0.5	21.7
Purchase of deferred compensation shares	(1.0)	(1.0)	(1.0)
Stock based compensation	5.4	5.4			7.5	(2.1)
Dividends on common stock	(211.8)	(211.8)				(211.8)
Other	11.2	11.2	2.4		9.5	(0.7)
Balance at Dec. 31, 2011	$ 3,012.6	$ 2,961.4	$ (17.1)	$ 78.3	$ 2,579.1	$ 363.6	$ (42.5)	$ 51.1	$ 0.1