CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Accounts receivable, allowances for bad debts and customer credits	$ 406	$ 740
Stockholders' equity:
Common stock, par value	$ 0.001	$ 0.001
Common stock, authorized	55,000,000	55,000,000
Common stock, issued	13,169,204	13,146,831
Common stock, outstanding	13,169,204	13,146,831
Series A Preferred Stock
Stockholders' equity:
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized	11,445,187	11,445,187
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0