Stock Based Compensation (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
Feb. 29, 2020	Mar. 02, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense (benefit)	$ 2.7	$ 2.7
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 7.2
Weighted average period of unrecognized compensation expense (in years)	2 years 3 months 18 days

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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.

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