Stockholders' Equity (Schedule of total comprehensive income (loss)) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
		Nov. 27, 2016	Nov. 29, 2015	Nov. 27, 2016	Nov. 29, 2015	May 29, 2016
Net earnings attributable to General Mills		$ 481.8	$ 529.5	$ 890.8	$ 956.1
Net earnings (loss) attributable to redeemable and noncontrolling interests		14.0	14.1	24.5	22.6
Other Comprehensive Income (Loss), Net of Tax:
Foreign currency translation		(105.7)	(70.3)	(25.3)	(212.5)
Other fair value changes:
Securities		(0.1)	0.1	0.3	0.0
Hedge derivatives		32.1	0.1	47.3	10.4
Reclassification to earnings:
Hedge derivatives		(7.8)	(0.3)	(10.6)	0.4
Amortization of losses and prior service costs		31.8	35.9	62.4	66.8
Other comprehensive income (loss), net of tax		(49.7)	(34.5)	74.1	(134.9)
Total comprehensive income (loss) attributable to General Mills		489.6	542.7	1,026.1	859.8
General Mills [Member]
Net earnings attributable to General Mills		481.8	529.5	890.8	956.1
Other Comprehensive Income (Loss), Pretax:
Foreign currency translation		(49.6)	(22.8)	37.0	(172.7)
Other fair value changes:
Securities		(0.1)	0.1	0.5	0.0
Hedge derivatives		48.5	2.1	58.7	15.3
Reclassification to earnings:
Hedge derivatives	[1]	(7.0)	(1.2)	(8.6)	(2.3)
Amortization of losses and prior service costs	[2]	51.4	57.7	100.8	107.4
Other comprehensive income (loss), before tax		43.2	35.9	188.4	(52.3)
Other Comprehensive Income (Loss), Tax:
Foreign currency translation		0.0	0.0	0.0	0.0
Other fair value changes:
Securities		0.0	0.0	(0.2)	0.0
Hedge derivatives		(16.0)	(1.1)	(14.1)	(4.2)
Reclassification to earnings:
Hedge derivatives	[1]	0.2	0.2	(0.4)	0.8
Amortization of losses and prior service costs	[2]	(19.6)	(21.8)	(38.4)	(40.6)
Other comprehensive income (loss), tax		(35.4)	(22.7)	(53.1)	(44.0)
Other Comprehensive Income (Loss), Net of Tax:
Foreign currency translation		(49.6)	(22.8)	37.0	(172.7)
Other fair value changes:
Securities		(0.1)	0.1	0.3	0.0
Hedge derivatives		32.5	1.0	44.6	11.1
Reclassification to earnings:
Hedge derivatives	[1]	(6.8)	(1.0)	(9.0)	(1.5)
Amortization of losses and prior service costs	[2]	31.8	35.9	62.4	66.8
Other comprehensive income (loss), net of tax		7.8	13.2	135.3	(96.3)
Total comprehensive income (loss) attributable to General Mills		489.6	542.7	1,026.1	859.8
Noncontrolling Interests [Member]
Net earnings (loss) attributable to redeemable and noncontrolling interests		6.0	3.9	7.8	6.5
Other Comprehensive Income (Loss), Net of Tax:
Foreign currency translation		(18.0)	(17.5)	(15.2)	(12.2)
Other fair value changes:
Securities		0.0	0.0	0.0	0.0
Hedge derivatives		0.0	0.0	0.0	0.0
Reclassification to earnings:
Hedge derivatives	[1]	0.0	0.0	0.0	0.0
Amortization of losses and prior service costs	[2]	0.0	0.0	0.0	0.0
Other comprehensive income (loss), net of tax		(18.0)	(17.5)	(15.2)	(12.2)
Total comprehensive income (loss) attributable to noncontrolling interests		(12.0)	(13.6)	(7.4)	(5.7)
Redeemable Interests [Member]
Net earnings (loss) attributable to redeemable and noncontrolling interests		8.0	10.2	16.7	16.1
Other Comprehensive Income (Loss), Net of Tax:
Foreign currency translation		(38.1)	(30.0)	(47.1)	(27.6)
Other fair value changes:
Securities		0.0	0.0	0.0	0.0
Hedge derivatives		(0.4)	(0.9)	2.7	(0.7)
Reclassification to earnings:
Hedge derivatives	[1]	(1.0)	0.7	(1.6)	1.9
Amortization of losses and prior service costs	[2]	0.0	0.0	0.0	0.0
Other comprehensive income (loss), net of tax		(39.5)	(30.2)	(46.0)	(26.4)
Total comprehensive income (loss) attributable to redeemable interests		$ (31.5)	$ (20.0)	$ (29.3)	$ (10.3)	$ 30.3

[1] (Gain) loss reclassified from AOCI into earnings is reported in interest, net for interest rate swaps and in cost of sales and selling, general, and administrative (SG&A) expenses for foreign exchange contracts.

[2] Loss reclassified from AOCI into earnings is reported in SG&A expenses.