RESTRUCTURING ACTIVITIES - Schedule of Liabilities Recorded for the Restructuring Plan (Details) $ in Millions	9 Months Ended
	Feb. 23, 2020 USD ($)
Pinnacle Integration Restructuring Plan
Restructuring Cost and Reserve
Beginning balance	$ 97.5
Costs Incurred and Charged to Expense	43.7
Costs Paid or Otherwise Settled	(98.8)
Changes in Estimates	(1.9)
Ending balance	40.5
Pinnacle Integration Restructuring Plan | Severance and related costs
Restructuring Cost and Reserve
Beginning balance	76.9
Costs Incurred and Charged to Expense	10.4
Costs Paid or Otherwise Settled	(52.6)
Changes in Estimates	(1.9)
Ending balance	32.8
Pinnacle Integration Restructuring Plan | Contract termination
Restructuring Cost and Reserve
Beginning balance	1.0
Costs Incurred and Charged to Expense	4.6
Costs Paid or Otherwise Settled	(3.9)
Changes in Estimates	0.0
Ending balance	1.7
Pinnacle Integration Restructuring Plan | Consulting/professional fees
Restructuring Cost and Reserve
Beginning balance	18.4
Costs Incurred and Charged to Expense	22.2
Costs Paid or Otherwise Settled	(34.6)
Changes in Estimates	0.0
Ending balance	6.0
Pinnacle Integration Restructuring Plan | Other costs
Restructuring Cost and Reserve
Beginning balance	1.2
Costs Incurred and Charged to Expense	6.5
Costs Paid or Otherwise Settled	(7.7)
Changes in Estimates	0.0
Ending balance	0.0
Conagra Restructuring Plan
Restructuring Cost and Reserve
Beginning balance	1.2
Costs Incurred and Charged to Expense	7.4
Costs Paid or Otherwise Settled	(3.3)
Changes in Estimates	(0.5)
Ending balance	4.8
Conagra Restructuring Plan | Severance and related costs
Restructuring Cost and Reserve
Beginning balance	1.2
Costs Incurred and Charged to Expense	5.6
Costs Paid or Otherwise Settled	(1.5)
Changes in Estimates	(0.5)
Ending balance	4.8
Conagra Restructuring Plan | Contract termination
Restructuring Cost and Reserve
Beginning balance	0.0
Costs Incurred and Charged to Expense	0.1
Costs Paid or Otherwise Settled	(0.1)
Changes in Estimates	0.0
Ending balance	0.0
Conagra Restructuring Plan | Other costs
Restructuring Cost and Reserve
Beginning balance	0.0
Costs Incurred and Charged to Expense	1.7
Costs Paid or Otherwise Settled	(1.7)
Changes in Estimates	0.0
Ending balance	$ 0.0