Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Allowance for doubtful accounts	$ 135	$ 275
Temporary equity, par value	$ 0.01	$ 0.01
Temporary equity, shares authorized	5,000,000	5,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	4,132,507	4,075,257
Common stock, shares outstanding	4,112,843	4,055,593
Treasury stock, shares	19,664	19,664
Series B [Member]
Temporary equity, shares issued	47,000	47,000
Temporary equity, shares outstanding	47,000	47,000

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

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