Consolidated Statements of Changes in Shareholders' Equity (USD $) In Millions		Total	Preferred Stock [Member]		Common Stock [Member]	Treasury Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]
Balance at beginning of period, Value at Dec. 31, 2008			$ 0	[1]	$ 40.6	$ (505.2)	$ 611.7	$ 1,062.6	$ (85.2)
Balance at beginning of period, Shares at Dec. 31, 2008			0		65.1	(16.3)
Issuance of common stock	[1]	0			0
Issuance of common stock, Shares					0.1
Stock repurchases						(55.1)
Stock repurchases, Shares		(2.8)				(2.8)
Share-based compensation effects							5.1
Net income		81.4						81.4
Dividends declared								(54.0)
Other comprehensive (loss) income		0.7							0.7
Balance at end of period, Value at Dec. 31, 2009		1,102.6	0	[1]	40.6	(560.3)	616.8	1,090.0	(84.5)
Balance at end of period, Shares at Dec. 31, 2009			0		65.2	(19.1)
Issuance of common stock					0.2		2.3
Issuance of common stock, Shares					0.2
Convertible debt conversions					0.1		(0.1)
Convertible debt conversions, shares					0.1
Stock repurchases, Shares		0
Share-based compensation effects							7.2
Net income		80.8						80.8
Dividends declared								(53.9)
Other comprehensive (loss) income		(25.5)							(25.5)
Balance at end of period, Value at Dec. 31, 2010		1,113.7	0	[1]	40.9	(560.3)	626.2	1,116.9	(110.0)
Balance at end of period, Shares at Dec. 31, 2010			0		65.5	(19.1)
Issuance of common stock					0.2		6.4
Issuance of common stock, Shares					0.3
Stock repurchases, Shares		0
Share-based compensation effects							11.8
Net income		110.8						110.8
Dividends declared								(56.5)
Other comprehensive (loss) income		(59.1)							(59.1)
Balance at end of period, Value at Dec. 31, 2011		$ 1,127.3	$ 0	[1]	$ 41.1	$ (560.3)	$ 644.4	$ 1,171.2	$ 169.1
Balance at end of period, Shares at Dec. 31, 2011			0		65.8	(19.1)

[1] Less than $0.1 million.