Discontinued Operations - Results of Discontinued Operations (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Discontinued Operations and Disposal Groups [Abstract]
Net Sales	$ 45	$ 1,890	$ 66	$ 9,715
Operating (loss) income of discontinued operations	(42)	(3,294)	19	(5,858)
Loss on disposal of discontinued operations		(231)		(231)
(Loss) income before income taxes	(42)	(3,525)	19	(6,089)
Income tax expense	0	0	0	0
(Loss) income from discontinued operations, net of taxes	$ (42)	$ (3,525)	$ 19	$ (6,089)

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
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