EARNINGS PER SHARE - Reconciliation of Income and Average Share Amounts Used to Compute Basic and Diluted Earnings (Loss) Per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Aug. 30, 2020	Aug. 25, 2019
Earnings Per Share [Abstract]
Net income attributable to Conagra Brands, Inc. common stockholders:	$ 329.0	$ 173.8
Weighted average shares outstanding:
Basic weighted average shares outstanding (in shares)	488.2	486.8
Add: Dilutive effect of stock options, restricted stock unit awards, and other dilutive securities (in shares)	1.7	1.1
Diluted weighted average shares outstanding (in shares)	489.9	487.9

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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