Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919359-209981

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- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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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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Related Party Transaction - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Feb. 27, 2021	Feb. 29, 2020	Feb. 27, 2021	Feb. 29, 2020
Related Party Transaction [Line Items]
Rental expense	$ 484,000	$ 481,000	$ 1,474,000	$ 1,427,000
Lessor - LDL, LLC \| Lee A. McIntyre III
Related Party Transaction [Line Items]
Total future minimum lease payments	$ 700,000		$ 700,000
Lease term	5 years		5 years
Lessor - LDL, LLC \| Lee A. McIntyre III \| Maximum
Related Party Transaction [Line Items]
Rental expense			$ 100,000	$ 100,000