Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2023	Jun. 30, 2022
Common Class A [Member]
Statement [Line Items]
Common Stock, Par value (in dollars per share)	$ 0.025	$ 0.025
Common Stock, Shares Authorized (in shares)	28,000,000	28,000,000
Common Stock, Shares, Issued (in shares)	13,866,999	13,866,999
Common Stock, Shares, Outstanding (in shares)	12,582,905	12,888,950
Treasury shares (in shares)	1,284,094	978,049
Common Class B [Member]
Statement [Line Items]
Common Stock, Par value (in dollars per share)	$ 0.025	$ 0.025
Common Stock, Shares Authorized (in shares)	4,500,000	4,500,000
Common Stock, Shares, Issued (in shares)	0	0
Common Class C [Member]
Statement [Line Items]
Common Stock, Par value (in dollars per share)	$ 0.025	$ 0.025
Common Stock, Shares Authorized (in shares)	3,500,000	3,500,000
Common Stock, Shares, Issued (in shares)	2,068,549	2,068,549
Common Stock, Shares, Outstanding (in shares)	2,068,549	2,068,549