CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 29, 2020	Nov. 24, 2019	Nov. 29, 2020	Nov. 24, 2019
Income Statement [Abstract]
Product sales	$ 130,904	$ 142,593	$ 266,547	$ 281,307
Cost of product sales	110,267	127,079	229,564	250,457
Gross profit	20,637	15,514	36,983	30,850
Operating costs and expenses:
Research and development	2,572	2,822	5,080	5,643
Selling, general and administrative	16,106	18,728	34,009	35,623
Legal settlement charge	1,763	0	1,763	0
Restructuring costs	1,662	0	10,066	0
Total operating costs and expenses	22,103	21,550	50,918	41,266
Operating loss	(1,466)	(6,036)	(13,935)	(10,416)
Dividend income	281	281	563	562
Interest income	10	25	18	50
Interest expense, net	(3,039)	(2,169)	(6,148)	(4,244)
Other (expense) income, net	(11,787)	(6)	(11,808)	(6)
Net loss before tax	(16,001)	(7,905)	(31,310)	(14,054)
Income tax benefit	2,700	1,165	7,009	2,530
Net loss	$ (13,301)	$ (6,740)	$ (24,301)	$ (11,524)
Net loss per common share:
Net loss per common share - basic (in dollars per share)	$ (0.45)	$ (0.23)	$ (0.83)	$ (0.40)
Net loss per common share - diluted (in dollars per share)	$ (0.45)	$ (0.23)	$ (0.83)	$ (0.40)
Net loss per common share:
Basic (in shares)	29,280	29,155	29,261	29,147
Diluted (in shares)	29,280	29,155	29,261	29,147
Other comprehensive income (loss), net of tax:
Net unrealized gain (loss) on interest rate swaps (net of tax effect of $(121), $(39), $(228), and $226)	$ 401	$ 127	$ 705	$ (485)
Other comprehensive income, net	401	127	705	(485)
Total comprehensive loss	$ (12,900)	$ (6,613)	$ (23,596)	$ (12,009)