Restructuring and related cost approved for incurrence cash outflows from inception.

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Restructuring and related cost approved for incurrence noncash charges from inception.

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Restructuring and related cost expected cash outflows.

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Restructuring and related cost expected noncash charges.

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Restructuring and related cost incurred cash outflows from inception.

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Restructuring and related cost incurred noncash charges from inception.

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Restructuring and related cost incurred or expected cash outflows from inception.

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Restructuring and related cost incurred or expected non cash charges from inception.

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Amount of costs incurred to date for the specified restructuring cost.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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RESTRUCTURING ACTIVITIES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended			18 Months Ended	76 Months Ended
	May 31, 2020	May 26, 2019	May 27, 2018	May 31, 2020	May 31, 2020	Dec. 31, 2018
Pinnacle Integration Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges approved for incurrence						$ 360.0
Cash charges approved for incurrence						255.0
Non-cash charges approved for incurrence						$ 105.0
Charges expected to be incurred	$ 360.2			$ 360.2	$ 360.2
Cash charges incurred or expected to be incurred	277.2			277.2	277.2
Non-cash charges incurred or expected to be incurred	83.0			83.0	83.0
Recognized charges	73.8	$ 168.2		242.0
Charges that have resulted or will result in cash outflows	51.2
Non-cash charges	22.6
Charges that have resulted or will result in cash outflows				212.4
Non-cash charges				29.6
Conagra Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Charges approved for incurrence	131.1			131.1	131.1
Cash charges approved for incurrence	38.2			38.2	38.2
Non-cash charges approved for incurrence	92.9			92.9	92.9
Charges expected to be incurred	129.5			129.5	129.5
Cash charges incurred or expected to be incurred	40.1			40.1	40.1
Non-cash charges incurred or expected to be incurred	89.4			89.4	89.4
Recognized charges	64.4	2.2		66.6
Charges that have resulted or will result in cash outflows	11.4
Non-cash charges	53.0
Charges that have resulted or will result in cash outflows				12.8
Non-cash charges				$ 53.8
SCAE Plan
Restructuring Cost And Reserve [Line Items]
Recognized charges	$ 1.3	$ 9.6	$ 38.0		471.2
Charges that have resulted or will result in cash outflows					322.0
Non-cash charges					149.2
SCAE Plan \| Cost of goods sold
Restructuring Cost And Reserve [Line Items]
Recognized charges					103.3
SCAE Plan \| Selling, general and administrative expenses
Restructuring Cost And Reserve [Line Items]
Recognized charges					365.6
SCAE Plan \| Reclassified to Pension and postretirement non-service income
Restructuring Cost And Reserve [Line Items]
Recognized charges					$ 2.3