Business Segment Reporting - Sales by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended
Aug. 30, 2020	Aug. 25, 2019
Segment Reporting Information [Line Items]
Product sales	$ 135,643	$ 138,714
Canada
Segment Reporting Information [Line Items]
Product sales	16,500	20,700
Belgium
Segment Reporting Information [Line Items]
Product sales	3,900	0
Ireland
Segment Reporting Information [Line Items]
Product sales	800	1,400
All Other Countries
Segment Reporting Information [Line Items]
Product sales	$ 1,700	$ 1,700

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details