INVESTMENTS IN JOINT VENTURES - Other Investments and Transactions with Ventures (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 26, 2017	Feb. 28, 2016	Feb. 26, 2017	Feb. 28, 2016	May 29, 2016
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 155.6		$ 155.6		$ 155.2
Lamb Weston RDO and Lamb Weston Meijer
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	155.6		155.6		$ 155.2
Sales	6.1	$ 2.0	20.8	$ 8.7
Payments	3.8	3.4	11.1	8.9
Dividends received from equity method investments	$ 8.2	$ 22.0	$ 22.1	$ 29.8
Lamb Weston/Meijer
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	50.00%		50.00%

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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The amount of the cost of sales reported by an equity method investment of the entity.

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