CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
ASSETS
Accounts receivable allowance	$ 84	$ 84
Stockholders' equity:
Common stock par value	$ 0.001	$ 0.001
Common stock shares authorized	24,500,000	24,500,000
Common stock outstanding	15,906,010	15,906,010
Common stock issued	15,906,010	15,906,010
Treasury stock shares	3,367,145	3,367,145

Amount of allowance for credit loss on accounts receivable, classified as current.

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