Business Segment and Geographic Information - Schedule of Operating Segment Results (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 23, 2025	Nov. 24, 2024	Nov. 23, 2025	Nov. 24, 2024
Segment Reporting Information [Line Items]
Net sales	$ 4,860.8	$ 5,240.1	$ 9,378.3	$ 10,088.2
Cost of sales	3,168.3	3,309.0	6,153.0	6,468.3
Selling, general, and administrative expenses	842.4	852.0	1,687.5	1,707.1
Operating profit	728.0	1,077.9	2,453.8	1,909.4
Divestitures gain	0.0	0.0	1,054.4	0.0
Restructuring, transformation, impairment, and other exit costs	122.1	1.2	138.4	3.4
Operating Segments
Segment Reporting Information [Line Items]
Net sales	4,854.4	5,237.9	9,366.8	10,083.8
Operating profit	938.6	1,143.9	1,752.0	2,101.4
Corporate and Joint Ventures
Segment Reporting Information [Line Items]
Net sales	6.4	2.2	11.5	4.4
Operating profit	88.5	64.8	214.2	188.6
North America Retail \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	2,883.3	3,321.5	5,508.8	6,338.1
Cost of sales	1,794.7	2,023.9	3,459.2	3,860.3
Selling, general, and administrative expenses	406.3	435.3	803.1	869.8
Operating profit	682.3	862.3	1,246.5	1,608.0
North America Retail \| Operating Segments \| U.S. Meals & Baking Solutions
Segment Reporting Information [Line Items]
Net sales	1,312.8	1,327.9	2,234.2	2,274.2
North America Retail \| Operating Segments \| Big G Cereal & Canada
Segment Reporting Information [Line Items]
Net sales	779.5	1,150.5	1,646.4	2,310.3
North America Retail \| Operating Segments \| U.S. Snacks
Segment Reporting Information [Line Items]
Net sales	791.0	843.1	1,628.2	1,753.6
International \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	728.9	690.6	1,489.1	1,407.6
Cost of sales	541.3	520.5	1,080.1	1,068.8
Selling, general, and administrative expenses	159.2	146.3	314.9	294.1
Operating profit	28.4	23.8	94.1	44.7
North America Pet \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	660.4	595.8	1,270.4	1,171.9
Cost of sales	394.2	341.6	762.8	679.7
Selling, general, and administrative expenses	143.1	114.9	271.6	233.5
Operating profit	123.1	139.3	236.0	258.7
North America Foodservice \| Operating Segments
Segment Reporting Information [Line Items]
Net sales	581.8	630.0	1,098.5	1,166.2
Cost of sales	433.5	466.6	835.8	887.7
Selling, general, and administrative expenses	43.5	44.9	87.3	88.5
Operating profit	$ 104.8	$ 118.5	$ 175.4	$ 190.0

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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