RESTRUCTURING ACTIVITIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		25 Months Ended	27 Months Ended
	Feb. 28, 2021	Feb. 23, 2020	Feb. 28, 2021	Feb. 23, 2020	Feb. 28, 2021	Feb. 28, 2021
Pinnacle Integration Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges expected to be incurred	$ 362.3		$ 362.3		$ 362.3	$ 362.3
Cash charges incurred or expected to be incurred	284.3		284.3		284.3	284.3
Non-cash charges incurred or expected to be incurred	78.0		78.0		78.0	78.0
Recognized charges	5.4	$ 19.6	24.2	$ 63.5		266.2
Charges that have resulted or will result in cash outflows	4.4		22.0
Non-cash charges	1.0		2.2
Charges that have resulted or will result in cash outflows						234.4
Non-cash charges						31.8
Conagra Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges expected to be incurred	157.4		157.4		157.4	157.4
Cash charges incurred or expected to be incurred	36.9		36.9		36.9	36.9
Non-cash charges incurred or expected to be incurred	120.5		120.5		120.5	120.5
Recognized charges	10.0	$ 11.9	37.8	$ 52.6	104.4
Charges that have resulted or will result in cash outflows	1.8		8.7
Non-cash charges	8.2		29.1
Charges that have resulted or will result in cash outflows					21.5
Non-cash charges					82.9
Charges approved for incurrence	171.0		171.0		171.0	171.0
Cash charges approved for incurrence	44.2		44.2		44.2	44.2
Non-cash charges approved for incurrence	$ 126.8		$ 126.8		$ 126.8	$ 126.8