RESTRUCTURING ACTIVITIES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended			30 Months Ended
	May 30, 2021	May 31, 2020	May 26, 2019	May 30, 2021
Pinnacle Integration Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges expected to be incurred	$ 358.0			$ 358.0
Cash charges incurred or expected to be incurred	283.5			283.5
Non-cash charges incurred or expected to be incurred	74.5			74.5
Recognized charges	31.7	$ 73.8	$ 168.2	273.7
Charges that have resulted or will result in cash outflows	28.5
Non-cash charges	3.2
Charges that have resulted or will result in cash outflows				240.9
Non-cash charges				32.8
Conagra Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges expected to be incurred	157.3			157.3
Cash charges incurred or expected to be incurred	36.9			36.9
Non-cash charges incurred or expected to be incurred	120.4			120.4
Recognized charges	46.2	$ 64.4	$ 2.2	112.8
Charges that have resulted or will result in cash outflows	11.3
Non-cash charges	34.9
Charges that have resulted or will result in cash outflows				24.1
Non-cash charges				88.7
Charges approved for incurrence	172.2			172.2
Cash charges approved for incurrence	45.4			45.4
Non-cash charges approved for incurrence	$ 126.8			$ 126.8