Note 1 - Organization, Basis of Presentation and Summary of Significant Accounting Policies (Tables)

9 Months Ended

Feb. 28, 2016

Notes Tables

Schedule of Effect of Significant Unobservable Inputs for Investment [TableText Block]

	At February 28, 2016		At May 31, 2015
Revenue growth rates		4%			4%
Expense growth rates		4%			4%
Income tax rates		15%			15%
Discount rates		12.5%		15%	to	21%

Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block]

Impact on value of Windset investment as of February 28, 2016
10% increase in revenue growth rates	$	700
10% increase in expense growth rates	$	(500	)
10% increase in income tax rates	$	—
10% increase in discount rates	$	(300	)

Revenue Recognition, Multiple-deliverable Arrangements [Table Text Block]

	Three months ended February 28, 2016		Three months ended March 1, 2015		Nine months ended February 28, 2016		Nine months ended March 1, 2015
Recorded upon shipment	$	118,789	$	128,502	$	341,914	$	344,506
Recorded upon acceptance in foreign port		6,389		8,086		50,873		56,779
Revenue from license fees, R&D contracts and royalties/profit sharing		787		153		3,327		788
Revenue from multiple element arrangements		4,025		1,789		9,672		2,736
Total	$	129,990	$	138,530	$	405,786	$	404,809