CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss
Balance (in shares) at May. 26, 2019			29,102
Balance at May. 26, 2019	$ 270,144	$ (274)	$ 29	$ 160,341	$ 109,710	$ (274)	$ 64
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under stock plans (in shares)			44
Issuance of stock under stock plans	0
Taxes paid by Company for employee stock plans	(55)			(55)
Stock-based compensation	528			528
Net loss	(4,784)				(4,784)
Other comprehensive income (loss), net of tax	(612)						(612)
Balance (in shares) at Aug. 25, 2019			29,146
Balance at Aug. 25, 2019	$ 264,947		$ 29	160,814	104,652		(548)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Balance (in shares) at May. 26, 2019			29,102
Balance at May. 26, 2019	$ 270,144	$ (274)	$ 29	160,341	109,710	$ (274)	64
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(11,524)
Other comprehensive income (loss), net of tax	(485)
Balance (in shares) at Nov. 24, 2019			29,163
Balance at Nov. 24, 2019	259,076		$ 29	161,556	97,912		(421)
Balance (in shares) at Aug. 25, 2019			29,146
Balance at Aug. 25, 2019	264,947		$ 29	160,814	104,652		(548)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under stock plans (in shares)			17
Issuance of stock under stock plans	30			30
Taxes paid by Company for employee stock plans	(75)			(75)
Stock-based compensation	787			787
Net loss	(6,740)				(6,740)
Other comprehensive income (loss), net of tax	127						127
Balance (in shares) at Nov. 24, 2019			29,163
Balance at Nov. 24, 2019	259,076		$ 29	161,556	97,912		(421)
Balance (in shares) at May. 31, 2020			29,224
Balance at May. 31, 2020	231,044		$ 29	162,578	71,245		(2,808)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under stock plans (in shares)			18
Issuance of stock under stock plans	0
Taxes paid by Company for employee stock plans	(82)			(82)
Stock-based compensation	892			892
Net loss	(11,000)				(11,000)
Other comprehensive income (loss), net of tax	304						304
Balance (in shares) at Aug. 30, 2020			29,242
Balance at Aug. 30, 2020	221,158		$ 29	163,388	60,245		(2,504)
Balance (in shares) at May. 31, 2020			29,224
Balance at May. 31, 2020	231,044		$ 29	162,578	71,245		(2,808)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(24,301)
Other comprehensive income (loss), net of tax	705
Balance (in shares) at Nov. 29, 2020			29,323
Balance at Nov. 29, 2020	208,938		$ 29	164,068	46,944		(2,103)
Balance (in shares) at Aug. 30, 2020			29,242
Balance at Aug. 30, 2020	221,158		$ 29	163,388	60,245		(2,504)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under stock plans (in shares)			81
Issuance of stock under stock plans	0
Taxes paid by Company for employee stock plans	(215)			(215)
Stock-based compensation	895			895
Net loss	(13,301)				(13,301)
Other comprehensive income (loss), net of tax	401						401
Balance (in shares) at Nov. 29, 2020			29,323
Balance at Nov. 29, 2020	$ 208,938		$ 29	$ 164,068	$ 46,944		$ (2,103)