Revenue recognition - Disaggregation of Revenue by Timing of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 23, 2025	Feb. 25, 2024	Feb. 23, 2025	Feb. 25, 2024
Segment Reporting Information [Line Items]
Revenues	$ 35,154	$ 35,704	$ 92,423	$ 90,375
Revenues recognized over time
Segment Reporting Information [Line Items]
Revenues	5,505	7,022	17,503	19,229
Revenues recognized at a point in time
Segment Reporting Information [Line Items]
Revenues	$ 29,649	$ 28,682	$ 74,920	$ 71,146

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