Stockholders' Equity (Schedule of total comprehensive income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	May 26, 2013	Feb. 24, 2013	Nov. 25, 2012	Aug. 26, 2012	May 27, 2012	Feb. 26, 2012	Nov. 27, 2011	Aug. 28, 2011	May 26, 2013	May 27, 2012	May 29, 2011	May 26, 2013 General Mills [Member]	May 27, 2012 General Mills [Member]	May 29, 2011 General Mills [Member]	May 26, 2013 Noncontrolling Interest [Member]	May 27, 2012 Noncontrolling Interest [Member]	May 29, 2011 Noncontrolling Interest [Member]	May 26, 2013 Redeemable Interest [Member]	May 27, 2012 Redeemable Interest [Member]	May 30, 2010 Redeemable Interest [Member]
Other Comprehensive Income (Loss) Before Tax [Abstract]
Foreign currency translation adjustments												$ (19.8)	$ (270.3)	$ 358.3
Net actuarial gain (loss)												76.3	(813.1)	93.5
Other fair value chages:
Securities												1.2	(0.3)	(5.8)
Hedge derivaties												33.5	(80.8)	(39.8)
Reclassification to earnings:
Hedge derivatives												15.0	16.3	29.8
Amortization of losses and prior service costs												159.9	131.6	108.7
Other comprehensive income (loss), before tax												266.1	(1,016.6)	544.7
Other Comprehensive Income (Loss), Tax [Abstract]
Foreign currency translation adjustments												0	0	0
Net actuarial gain												(31.3)	308.5	(32.4)
Other fair value changes:
Securities												(0.4)	0.1	2.2
Hedge derivatives												(10.4)	31.2	14.4
Reclassification to earnings:
Hedge derivatives												(4.5)	(6.2)	(11.3)
Amortization of losses and prior service costs												(61.1)	(49.9)	(41.5)
Other Comprehensive Income (Loss), Tax												(107.7)	283.7	(68.6)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments									0.8	(420.1)	359.0	(19.8)	(270.3)	358.3	10.3	(51.1)	0.7	10.3	(98.7)
Net actuarial gain (loss)									45.0	(504.6)	61.1	45.0	(504.6)	61.1	0	0	0	0	0
Other fair value changes:
Securities									0.8	(0.2)	(3.6)	0.8	(0.2)	(3.6)	0	0	0	0	0
Hedge derivatives									24.6	(53.4)	(25.4)	23.1	(49.6)	(25.4)	0	0	0	1.5	(3.8)
Reclassification to earnings:
Hedge derivatives									12.2	11.5	18.5	10.5	10.1	18.5	0	0	0	1.7	1.4
Amortization of losses and prior service costs									98.8	81.7	67.2	98.8	81.7	67.2	0	0	0	0	0
Other comprehensive income (loss), net of tax									182.2	(885.1)	476.8	158.4	(732.9)	476.1	10.3	(51.1)	0.7	13.5	(101.1)
Comprehensive Income:
Net earnings attributable to General Mills	366.3	398.4	541.6	548.9	325.4	391.5	444.8	405.6	1,855.2	1,567.3	1,798.3
Net earnings attributable to noncontrolling interests									8.0	6.8	5.2
Net earnings attributable to redeemable interest									29.3	15.0
Total comprehensive income (loss) attributable to General Mills									2,013.6	834.4	2,274.4
Total comprehensive income (loss) attributable to noncontrolling interests									18.3	(44.3)	5.9
Total comprehensive income (loss) attributable to redeemable interests									$ 42.8	$ (86.1)								$ 42.8	$ (86.1)