Balance Sheets (Unaudited) (Parentheticals) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	20,000,000	20,000,000
Common stock, issued shares (in shares)	14,601,487	14,460,486
Common stock, outstanding shares (in shares)	14,519,215	14,450,470
Treasury stock, shares (in shares)	82,272	10,016