Related Party Transactions - Additional Information (Detail) - USD ($)	12 Months Ended
May 31, 2019	May 31, 2018	May 31, 2017
Related Party Transactions [Abstract]
Net sales to affiliates	$ 53,125,000	$ 57,382,000	$ 56,588,000
Purchases from affiliates	2,906,000	7,292,000	$ 7,145,000
Receivables from affiliates	4,246,000	2,479,000
Payable to affiliates	$ 687,000	$ 0

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03.10(3))
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Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

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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.

+ References

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-Publisher FASB
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