CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parentheticals) - Common Stock [Member] - shares	3 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Common Class A [Member]
Balance	13,866,913	13,866,751
Balance	13,866,913	13,866,811
Purchases of shares of Common Stock (class A)	1,000	1,400
Issuance of stock under ESPP shares of Common Stock (class A)	267	314
Number of shares issued as result of stock conversion		60
Common Class C [Member]
Balance	2,068,635	2,068,797
Balance	2,068,635	2,068,737
Number of shares converted		(60)

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

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of shares that have been repurchased during the period and are being held in treasury.

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