Earnings Per Share and Dividends (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2012	Jun. 30, 2011
Earnings Per Share, Diluted [Abstract]
Basic weighted-average shares outstanding (in shares)	610.9		631.1		615.0	639.0
Common stock equivalents (in shares)	2.2		4.7		2.5	5.0
Diluted weighted-average shares outstanding (in shares)	613.1		635.8		617.5	644.0
Earnings per share and Dividends [Abstract]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	24.1		8.2		22.3	8.0
Cash dividends declared, per share (in dollars per share)	$ 0.10	$ 0.10	$ 0.08	$ 0.07	$ 0.20	$ 0.15
Cash dividends declared	$ 60.7	$ 61.6	$ 50.3	$ 44.7	$ 122.3	$ 95.0
Cash dividends paid	$ 60.7	$ 61.6	$ 50.3	$ 44.7	$ 122.3	$ 95.0

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details

- Definition

Cash outflow in the form of ordinary dividends to common shareholders, generally out of earnings.

+ References+ Details

- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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-URI http://asc.fasb.org/extlink&oid=6528421

+ Details