Consolidated Statements of Stockholders' Equity and Comprehensive Income (Loss) (USD $) In Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive (Loss) Gain	Retained Earnings
Beginning Balance at May. 31, 2008	$ 305,888	$ 523	$ 249,033	$ (182,707)	$ 8,534	$ 230,505
Beginning Balance, shares at May. 31, 2008		52,294		7,640
Exercise of stock options	7,600	6	7,594
Exercise of stock options, shares		624
Stock-based compensation expense related to share-based awards and employee stock purchases	17,790		17,790
Tax benefit/shortfall from employee stock option plans	420		420
Issuance/Release of restricted stock	250	1	249
Issuance/Release of restricted stock, shares		11
Issuance of treasury stock for acquisitions	1,260		(361)	1,621
Issuance of treasury stock for acquisitions, shares				(87)
Issuance of common stock under Employee Stock Purchase Plan	8,029	5	8,024
Issuance of common stock under Employee Stock Purchase Plan, shares		545
Issuance of treasury stock per employment agreements	98		20	78
Issuance of treasury stock per employment agreements, shares				(4)
Purchase of shares	(12,341)			(12,341)
Purchase of shares, shares				785
Comprehensive Income (Loss) :
Currency translation adjustment	(8,841)				(8,841)
Net income (loss)	17,764					17,764
Total comprehensive income (loss)	8,923
Ending Balance at May. 30, 2009	337,917	535	282,769	(193,349)	(307)	248,269
Ending Balance, shares at May. 30, 2009		53,474		8,334
Exercise of stock options	4,521	4	4,517
Exercise of stock options, shares		419
Stock-based compensation expense related to share-based awards and employee stock purchases	15,437		15,437
Tax benefit/shortfall from employee stock option plans	(1,127)		(1,127)
Issuance/Release of restricted stock	56		56
Issuance/Release of restricted stock, shares		4
Issuance of treasury stock for acquisitions	16,137		(496)	21,119		(4,486)
Issuance of treasury stock for acquisitions, shares				(822)
Issuance of common stock under Employee Stock Purchase Plan	5,280	4	5,276
Issuance of common stock under Employee Stock Purchase Plan, shares		370
Issuance of treasury stock per employment agreements	88		(19)	107
Issuance of treasury stock per employment agreements, shares				(6)
Purchase of shares	(9,042)			(9,042)
Purchase of shares, shares				496
Comprehensive Income (Loss) :
Currency translation adjustment	(4,277)				(4,277)
Net income (loss)	(11,749)					(11,749)
Total comprehensive income (loss)	(16,026)
Ending Balance at May. 29, 2010	353,241	543	306,413	(181,165)	(4,584)	232,034
Ending Balance, shares at May. 29, 2010		54,267		8,002
Exercise of stock options	4,546	4	4,542
Exercise of stock options, shares		379
Stock-based compensation expense related to share-based awards and employee stock purchases	9,669		9,669
Tax benefit/shortfall from employee stock option plans	(390)		(390)
Issuance/Release of restricted stock	88		88
Issuance/Release of restricted stock, shares		10
Issuance of common stock under Employee Stock Purchase Plan	4,152	3	4,149
Issuance of common stock under Employee Stock Purchase Plan, shares		365
Issuance of treasury stock per earn-out agreement	269			338		(69)
Issuance of treasury stock per earn-out agreement, shares				(15)
Issuance of restricted stock out of treasury stock to board of director members	21		21	483		(483)
Issuance of restricted stock out of treasury stock to board of director members, shares				(21)
Purchase of shares	(24,397)			(24,397)
Purchase of shares, shares				1,666
Cash dividends ($0.16 per share)	(7,354)					(7,354)
Comprehensive Income (Loss) :
Currency translation adjustment	8,026				8,026
Net income (loss)	24,855					24,855
Total comprehensive income (loss)	32,881
Ending Balance at May. 28, 2011	$ 372,726	$ 550	$ 324,492	$ (204,741)	$ 3,442	$ 248,983
Ending Balance, shares at May. 28, 2011		55,021		9,632