Earnings Per Share, Other Disclosures (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Potential dilutive effect of options and Warrants
Options outstanding to purchase common shares	20,791	20,791		20,791
Average exercise price per share	$ 80.01	$ 80.01		$ 80.01
Potential dilutive effect of shares underlying the options		0	0
Potential dilutive effect of shares underlying the Warrants		0	0
Dividends
Payment of cash dividends to stockholders		$ 9.8	$ 9.4
Cash dividend paid per share	$ 0.25	$ 0.50	$ 0.48
Warrant Transactions
Potential dilutive effect of options and Warrants
Number of common shares underlying the Warrants outstanding	3,600,000	3,600,000
Average Exercise price of common shares underlying warrants	61.32	61.32

The exercise price of each class of warrants or rights outstanding.

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