Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jul. 31, 2023	Jul. 31, 2022
Allowance for doubtful accounts	$ 1,087	$ 922
Trademarks and patents accumulated amortization	578	524
Customer list accumulated amortization	7,763	7,608
Unamortized debt issuance costs	$ 173	$ 202
Common Stock
Common Stock, shares issued	8,750,223	8,686,768
Common Stock, par value per share	$ 0.10	$ 0.10
Treasury Stock, shares	3,658,989	3,609,938
Class B
Common Stock, shares issued	2,397,056	2,397,056
Common Stock, par value per share	$ 0.10	$ 0.10
Treasury Stock, shares	351,641	351,641

Accumulated amortization as of the balance sheet date that pertains to a customer list finite-lived intangible asset.

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- Definition

The accumulated amount of amortization of the costs pertaining to the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit PLUS the accumulated amount of amortization of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524

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-Publisher FASB
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- Definition

Face amount or stated value per share of common stock.

+ References

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 30
-Section 45
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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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