Discontinued Operations - Results of Discontinued Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2016	May 31, 2015
Discontinued Operations and Disposal Groups [Abstract]
Net Sales	$ 71	$ 9,676
Operating loss of discontinued operations	(195)	(5,986)
Loss on disposal of discontinued operations		(240)
Loss before income taxes	(195)	(6,226)
Income tax benefit	0	0
Loss from discontinued operations, net of taxes	$ (195)	$ (6,226)

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.

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Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount of tax expense (benefit) attributable to income (loss) from operations classified as a discontinued operation. Excludes tax expense (benefit) for gain (loss) on disposal and for provision for gain (loss) until disposal.

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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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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.

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