Discontinued Operations - Results of Discontinued Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2017	May 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Net Sales		$ 71
Operating loss of discontinued operations		(195)
Income (loss) before income taxes		(195)
Income tax expense	$ 0	0
Income (loss) from discontinued operations, net of taxes		$ (195)

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 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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