Segment Reporting - Schedule of Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 29, 2020	Mar. 02, 2019	Feb. 29, 2020	Mar. 02, 2019
Segment Reporting Information [Line Items]
Net Sales	$ 38,249	$ 39,018	$ 118,536	$ 124,489
Gross Profit	12,670	12,299	38,301	39,223
PMT
Segment Reporting Information [Line Items]
Net Sales	28,988	29,725	89,158	96,822
Gross Profit	9,519	9,406	28,547	30,520
Canvys
Segment Reporting Information [Line Items]
Net Sales	7,200	6,954	22,333	20,625
Gross Profit	2,362	2,281	7,268	6,726
Healthcare
Segment Reporting Information [Line Items]
Net Sales	2,061	2,339	7,045	7,042
Gross Profit	$ 789	$ 612	$ 2,486	$ 1,977

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Paragraph 2
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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-Name Accounting Standards Codification
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