Subsequent Events	3 Months Ended
Aug. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	NOTE R – Subsequent Events On October 13, 2020, the Company sold its cryogenic trailer and hydrogen trailer business, including the Theodore, Alabama manufacturing site, to Chart Industries, Inc. for total proceeds of $10,000,000 subject to post-closing adjustments. The Company estimates the sale will generate a loss of approximately $4,000,000, primarily related to the allocation of goodwill.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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