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. 22, 2026	Feb. 23, 2025	Feb. 22, 2026	Feb. 23, 2025
Segment Reporting Information [Line Items]
Net sales	$ 4,436.7	$ 4,842.2	$ 13,815.0	$ 14,930.4
Snacks
Segment Reporting Information [Line Items]
Net sales	962.6	996.0	3,030.2	3,157.8
Cereal
Segment Reporting Information [Line Items]
Net sales	762.7	762.8	2,321.1	2,385.4
Convenient meals
Segment Reporting Information [Line Items]
Net sales	730.3	754.1	2,208.1	2,228.1
Pet
Segment Reporting Information [Line Items]
Net sales	678.1	651.7	2,019.8	1,880.1
Dough
Segment Reporting Information [Line Items]
Net sales	618.6	647.5	1,854.6	1,887.9
Baking mixes and ingredients
Segment Reporting Information [Line Items]
Net sales	476.1	467.5	1,480.1	1,501.8
Super-premium ice cream
Segment Reporting Information [Line Items]
Net sales	147.7	137.5	544.9	514.0
Yogurt
Segment Reporting Information [Line Items]
Net sales	0.0	333.1	102.0	1,082.8
Other
Segment Reporting Information [Line Items]
Net sales	$ 60.6	$ 92.0	$ 254.2	$ 292.5