Business Segment and Geographic Information (Schedule of net sales by class of similar products) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 24, 2019	Feb. 25, 2018	Feb. 24, 2019	Feb. 25, 2018
Product Information [Line Items]
Net sales	$ 4,198.3	$ 3,882.3	$ 12,703.5	$ 11,850.2
Snacks [Member]
Product Information [Line Items]
Net sales	815.6	819.1	2,502.8	2,514.5
Convenient meals [Member]
Product Information [Line Items]
Net sales	720.9	729.5	2,033.4	2,058.7
Cereal [Member]
Product Information [Line Items]
Net sales	668.4	649.4	2,000.6	2,009.8
Yogurt [Member]
Product Information [Line Items]
Net sales	533.0	574.3	1,630.4	1,722.0
Dough [Member]
Product Information [Line Items]
Net sales	442.3	441.7	1,309.0	1,304.7
Baking mixes and ingredients [Member]
Product Information [Line Items]
Net sales	401.7	398.1	1,255.6	1,279.1
Pet [Member]
Product Information [Line Items]
Net sales	346.8	0.0	1,025.3	0.0
Super-premium ice cream [Member]
Product Information [Line Items]
Net sales	157.1	153.3	607.4	584.4
Vegetables [Member]
Product Information [Line Items]
Net sales	66.2	66.9	204.1	226.2
Other [Member]
Product Information [Line Items]
Net sales	$ 46.3	$ 50.0	$ 134.9	$ 150.8