CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED BALANCE SHEETS
Allowance for doubtful accounts	$ 250,000	$ 250,000
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized	4,000,000	4,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	35,000,000	35,000,000
Common stock, shares issued	23,526,517	23,335,855
Common stock, shares outstanding	23,478,072	23,287,410
Treasury stock, shares	48,445	48,445