Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
CURRENT ASSETS:
Allowance for doubtful accounts	$ 14	$ 16
Accumulated amortization	$ 547	$ 547
STOCKHOLDERS' EQUITY:
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0024	$ 0.0024
Common stock, shares authorized (in shares)	25,000,000	25,000,000
Common stock, shares issued (in shares)	10,467,367	10,446,563
Treasury stock, shares (in shares)	1,424,376	1,424,376
Accumulated other comprehensive loss, tax	$ 432	$ 359