Investments in Unconsolidated Joint Ventures (Schedule of joint venture earnings and cash flow activity) (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 26, 2019	May 27, 2018
Schedule of Equity Method Investments [Line Items]
Net advances (repayments)	$ 48.0	$ (0.1)	$ 17.3
Dividends received	76.5	86.7	113.2
Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Sales to joint ventures	5.9	4.2	7.4
Net advances (repayments)	48.0	(0.1)	17.3
Dividends received	$ 76.5	$ 86.7	$ 113.2

The net cash inflow (outflow) associated with the payments received (advances to) an entity in which the reporting entity shares control of the entity with another party or group.

No definition available.

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21D
-URI http://asc.fasb.org/extlink&oid=118932676&loc=SL94080555-108585

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- Definition

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.

+ References

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=116637345&loc=SL114874292-224272

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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-03.1(e))
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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