CONSOLIDATED CONDENSED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Accounts receivable, allowances for bad debts and customer credits	$ 615	$ 892
Stockholders' equity:
Preferred stock, authorized	11,445,187	11,445,187
Common stock, par value	$ 0.001	$ 0.001
Common stock, authorized	55,000,000	55,000,000
Common stock, issued	12,948,950	13,059,341
Common stock, outstanding	12,948,950	13,059,341
Preferred Class A [Member]
Stockholders' equity:
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0