Earnings Per Share (Narrative) (Details) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share
Potential shares outstanding			3.2	2.4
Potential shares outstanding, not included in the diluted earnings per share calculation	2.6	2.0	2.6	2.1

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Balance Type:

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