Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 2,559	$ 2,263
Series A convertible preferred stock, par value (in dollars per share)	$ 0.0001
Series A convertible preferred stock, shares authorized (in shares)	400,000
Series A convertible preferred stock, shares issued (in shares)	400,000
Series A convertible preferred stock, shares outstanding (in shares)	400,000
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	235,690,000	219,422,000
Common stock, shares outstanding (in shares)	235,690,000	219,422,000
Treasure stock (in shares)	1,778,000	3,333,000

Amount of allowance for credit loss on accounts receivable.

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