Earnings Per Share (Schedule of earnings per share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended								12 Months Ended
		May 29, 2016	Feb. 28, 2016	Nov. 29, 2015	Aug. 30, 2015	May 31, 2015	Feb. 22, 2015	Nov. 23, 2014	Aug. 24, 2014	May 29, 2016	May 31, 2015	May 25, 2014
EARNINGS PER SHARE [Abstract]
Net earnings attributable to General Mills		$ 379.6	$ 361.7	$ 529.5	$ 426.6	$ 186.8	$ 343.2	$ 346.1	$ 345.2	$ 1,697.4	$ 1,221.3	$ 1,824.4
Average number of common shares - basic EPS										598.9	603.3	628.6
Earnings Per Share, Basic and Diluted [Abstract]
Average number of common shares - diluted EPS										611.9	618.8	645.7
Earnings per share - basic		$ 0.63	$ 0.61	$ 0.88	$ 0.71	$ 0.31	$ 0.57	$ 0.58	$ 0.56	$ 2.83	$ 2.02	$ 2.9
Earnings per share - diluted		$ 0.62	$ 0.59	$ 0.87	$ 0.69	$ 0.3	$ 0.56	$ 0.56	$ 0.55	$ 2.77	$ 1.97	$ 2.83
Other Disclosures [Abstract]
Anti-dilutive stock options, restricted stock units, and performance share units										1.1	2.1	1.7
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect	[1]									9.8	11.3	12.3
Restricted stock units, performance shares units, and other [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect	[1]									3.2	4.2	4.8

[1] Increme ntal shares from stock options , restricted stock units , and performance share units are computed by the treasury stock method.