Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jul. 31, 2022	Apr. 30, 2022
Current Assets:
Allowance for receivables	$ 371	$ 357
Stockholders' Equity:
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	5,000	5,000
Common stock, shares issued (in shares)	2,832	2,793
Common stock, shares outstanding (in shares)	2,829	2,790
Treasury stock, shares (in shares)	3	3

Amount of allowance for credit loss on accounts receivable, classified as current.

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