Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2021	Jun. 30, 2020
Statement Of Financial Position [Abstract]
Preferred shares, authorized	2,000,000	2,000,000
Preferred shares, unissued	2,000,000	2,000,000
Common shares, without par value
Common shares, authorized	12,000,000	12,000,000
Common shares, issued	6,924,000	6,899,000
Common shares, outstanding	6,924,000	6,899,000

Face amount per share of no-par value common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The number of nonredeemable preferred stock (shares) (or preferred stock redeemable solely at the option of the issuer) allocated to investors to buy shares of a new issue of preferred stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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