Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Related Party Transactions [Abstract]
Net sales to affiliates	$ 57,382	$ 56,588	$ 32,496
Purchases from affiliates	7,292	7,145	$ 15,737
Receivables from affiliates	2,479	4,616
Payable to affiliates	$ 0	$ 76

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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