Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
ASSETS
Other physical property, accumulated depreciation	$ 449	$ 435
CURRENT ASSETS:
Accounts receivables, reserves	$ 410	$ 305
COMMON STOCKHOLDERS' EQUITY:
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	46,500,000	46,500,000
Common stock, issued (in shares)	13,033,999	13,014,898
Common stock, outstanding (in shares)	13,033,999	13,014,898
Preferred stock, authorized (in shares)	500,000	500,000
Preferred stock, issued (in shares)	0	0