Earnings Per Share (Details) (USD $) In Millions, except Per Share data	3 Months Ended	12 Months Ended
May 29, 2011	Feb. 27, 2011	Nov. 28, 2010	Aug. 29, 2010	May 30, 2010	Feb. 28, 2010	Nov. 29, 2009	Aug. 30, 2009	May 29, 2011	May 30, 2010	May 31, 2009
Schedule Of Earnings Per Share [Abstract]
Net earnings attributable to General Mills	$ 320.2	$ 392.1	$ 613.9	$ 472.1	$ 211.9	$ 332.5	$ 565.5	$ 420.6	$ 1,798.3	$ 1,530.5	$ 1,304.4
Weighted Average Number Of Shares Outstanding Basic									642.7	659.6	663.7
Amount Of Dilutive Securities Stock Options	16.6				17.7				16.6	17.7	17.9
Amount of Dilutive Securities Restricted Stock Units									5.5	6.0	5.5
Weighted Average Number Of Diluted Shares Outstanding									664.8	683.3	687.1
Earnings per share - basic	$ 0.50	$ 0.61	$ 0.96	$ 0.73	$ 0.32	$ 0.50	$ 0.86	$ 0.64	$ 2.80	$ 2.32	$ 1.96
Earnings per share - diluted	$ 0.48	$ 0.59	$ 0.92	$ 0.70	$ 0.31	$ 0.48	$ 0.83	$ 0.62	$ 2.6950	$ 2.24	$ 1.90
Earnings Per Share Diluted Other Disclosures Abstract
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount									4.8	6.3	14.2

The number of incremental shares from restricted stock units used in computing the dilutive effect of convertible securities.

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The number of incremental shares from stock options used in computing the dilutive effect of convertible securities.

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

+ References

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The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

+ References

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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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-Publisher FASB
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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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

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