Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Allowance for bad debts	$ 4,982,000	$ 214,000
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	47,985,184	47,310,846
Common stock - shares outstanding	43,304,461	42,630,123
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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