DISCONTINUED OPERATIONS AND OTHER DIVESTITURES - Lamb Weston Spinoff (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 26, 2018	Aug. 27, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
After-tax loss related to disposal of Lamb Weston business	$ 0.0	$ 0.3
Pre-tax gains from sales of businesses	$ 13.3	0.0
Lamb Weston \| Discontinued operations, spinoff \| Lamb Weston
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
After-tax loss related to disposal of Lamb Weston business		0.2
Pre-tax loss related to disposal of Lamb Weston business		(0.3)
Lamb Weston \| Discontinued operations, spinoff \| Spinoff \| Transition services agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from transition services agreement		$ 1.3

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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