Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2012	Nov. 30, 2011
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 1,969	$ 2,329	$ 1,248	$ 3,702
Other comprehensive income (loss), before tax:
Unrealized gain (loss) on marketable securities	151	(214)	184	(276)
Unrealized gain (loss) on interest rate swap	29	2	(1,059)	(57)
Foreign currency translation gain (loss)	82	(113)	123	(113)
Other comprehensive income (loss), before tax	262	(325)	(752)	(446)
Income tax (expense) benefit related to items of other comprehensive income	(67)	78	324	123
Other comprehensive income (loss), net of tax	195	(247)	(428)	(323)
Total comprehensive income, net of tax	$ 2,164	$ 2,082	$ 820	$ 3,379

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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