INVESTMENTS IN JOINT VENTURES - Equity Method Investments - Fees Received (Details) - Equity Method Investee - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 26, 2019	May 27, 2018
Related Party Transactions
Revenue from related parties	$ 27.8	$ 29.9	$ 29.3
Fees for Services Provided \| Lamb-Weston Meijer v.o.f.
Related Party Transactions
Revenue from related parties	1.6	1.8	1.7
Fees for Services Provided \| Lamb-Weston RDO Frozen
Related Party Transactions
Revenue from related parties	$ 14.1	$ 14.8	$ 14.4

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874292-224272

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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