BUSINESS SEGMENTS AND RELATED INFORMATION (Net Sales by Product) (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
Segment Reporting Information [Line Items]
Total net sales	$ 4,593.5	$ 3,850.5	$ 3,735.5	$ 3,311.9	$ 3,434.9	$ 3,396.0	$ 3,431.7	$ 3,105.3	$ 15,491.4	$ 13,367.9	$ 12,386.1
Commercial Foods
Segment Reporting Information [Line Items]
Total net sales									5,167.4	4,991.1	4,384.1
Commercial Foods | Specialty Potatoes
Segment Reporting Information [Line Items]
Total net sales									2,753.1	2,631.0	2,375.3
Commercial Foods | Milled Products
Segment Reporting Information [Line Items]
Total net sales									1,957.3	1,910.2	1,603.5
Commercial Foods | Seasonings Blends and Flavors
Segment Reporting Information [Line Items]
Total net sales									457.0	449.9	405.3
Consumer Foods
Segment Reporting Information [Line Items]
Total net sales									9,069.9	8,376.8	8,002.0
Consumer Foods | Grocery
Segment Reporting Information [Line Items]
Total net sales									3,367.0	3,358.0	3,258.7
Consumer Foods | Frozen
Segment Reporting Information [Line Items]
Total net sales									2,383.8	1,990.6	1,965.2
Consumer Foods | Snacks
Segment Reporting Information [Line Items]
Total net sales									1,243.8	1,237.6	1,209.8
Consumer Foods | International
Segment Reporting Information [Line Items]
Total net sales									1,059.4	841.5	714.2
Consumer Foods | Store Brands
Segment Reporting Information [Line Items]
Total net sales									697.3	631.9	528.8
Consumer Foods | Other Brands
Segment Reporting Information [Line Items]
Total net sales									318.6	317.2	325.3
Ralcorp Frozen Bakery Products
Segment Reporting Information [Line Items]
Total net sales										0	0
Ralcorp
Segment Reporting Information [Line Items]
Total net sales									924.2	0	0
Ralcorp | Cereal
Segment Reporting Information [Line Items]
Total net sales									209.0	0	0
Ralcorp | Snacks
Segment Reporting Information [Line Items]
Total net sales									516.6	0	0
Ralcorp | Pasta
Segment Reporting Information [Line Items]
Total net sales									198.6	0	0
Ralcorp | Ralcorp Frozen Bakery Products
Segment Reporting Information [Line Items]
Total net sales									$ 329.9	$ 0	$ 0