Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Accretive [Member] Common Stock [Member]	Accretive [Member] Additional Paid-in Capital [Member]	Accretive [Member]	Taskforce [Member] Common Stock [Member]	Taskforce [Member] Additional Paid-in Capital [Member]	Taskforce [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Total
Balances at May. 27, 2017							$ 590	$ 398,828	$ (481,904)	$ (11,396)	$ 332,024	$ 238,142
Balances (in shares) at May. 27, 2017							58,992,000		29,330,000
Exercise of stock options							$ 6	6,483				6,489
Exercise of stock options (in shares)							517,000
Stock-based compensation expense								5,978				5,978
Issuance of common stock under Employee Stock Purchase Plan							$ 3	3,947				3,950
Issuance of common stock under Employee Stock Purchase Plan (in shares)							339,000
Issuance of restricted stock							$ 1	(1)
Issuance of restricted stock (in shares)							105,000
Issuance of restricted stock out of treasury stock to board of director members									$ 298		(298)
Issuance of restricted stock out of treasury stock to board of director members (in shares)									(13,000)
Purchase of shares									$ (5,116)			(5,116)
Purchase of shares (in shares)									321,000
Cash dividends declared											(14,811)	(14,811)
Issuance of common stock for acquisition	$ 11	$ 11,743	$ 11,754	$ 2	$ 2,600	$ 2,602
Issuance of common stock for acquisition (in shares)	1,072,000			227,000
Currency translation adjustment										1,011		1,011
Net income											18,826	18,826
Balances at May. 26, 2018							$ 613	429,578	$ (486,722)	(10,385)	335,741	268,825
Balances (in shares) at May. 26, 2018							61,252,000		29,638,000
Exercise of stock options							$ 15	19,794				19,809
Exercise of stock options (in shares)							1,444,000
Stock-based compensation expense								6,358				6,358
Issuance of common stock under Employee Stock Purchase Plan							$ 3	4,496				4,499
Issuance of common stock under Employee Stock Purchase Plan (in shares)							358,000
Issuance of restricted stock out of treasury stock to board of director members									$ 510		(510)
Issuance of restricted stock out of treasury stock to board of director members (in shares)									(21,000)
Purchase of shares									$ (29,891)			(29,891)
Purchase of shares (in shares)									1,849,000
Cash dividends declared											(16,471)	(16,471)
Currency translation adjustment										(2,203)		(2,203)
Net income											31,470	31,470
Balances at May. 25, 2019							$ 631	460,226	$ (516,103)	(12,588)	350,230	$ 282,396
Balances (in shares) at May. 25, 2019							63,054,000		31,466,000			31,588,000
Exercise of stock options							$ 3	5,122				$ 5,125
Exercise of stock options (in shares)							376,000					376,000
Stock-based compensation expense								5,833				$ 5,833
Issuance of common stock under Employee Stock Purchase Plan							$ 4	5,127				5,131
Issuance of common stock under Employee Stock Purchase Plan (in shares)							400,000
Cancellation of restricted stock (in shares)							(13,000)
Issuance of restricted stock (in shares)							10,000
Issuance of restricted stock out of treasury stock to board of director members								(10)	$ 15		(5)
Issuance of restricted stock out of treasury stock to board of director members (in shares)									(18,000)
Purchase of shares									$ (5,000)			(5,000)
Purchase of shares (in shares)									318,000
Cash dividends declared											(17,976)	(17,976)
Issuance of common stock for acquisition							$ 1	1,140				1,141
Issuance of common stock for acquisition (in shares)							83,000
Currency translation adjustment										(1,274)		(1,274)
Net income											28,285	28,285
Balances at May. 30, 2020							$ 639	$ 477,438	$ (521,088)	$ (13,862)	$ 360,534	$ 303,661
Balances (in shares) at May. 30, 2020							63,910,000		31,766,000			32,144,000