Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Allowance for bad debts	$ 1,043,000	$ 4,122,000
Preferred stock - par value	$ 0.001	$ 0.001
Preferred stock - shares authorized	5,000,000	5,000,000
Preferred stock - shares issued	0	0
Common stock - par value	$ 0.001	$ 0.001
Common stock - shares authorized	75,000,000	75,000,000
Common stock - shares issued	49,072,852	48,142,267
Common stock - shares outstanding	44,392,129	43,461,544
Treasury stock - shares	4,680,723	4,680,723

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

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