Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Allowance for credit loss	$ 4,403,000	$ 4,603,000
Undesignated preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Undesignated preferred stock, authorized (in shares)	32,659,235	32,659,235
Undesignated preferred stock, issued (in shares)	0	0
Undesignated preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	700,000,000	700,000,000
Common stock, issued (in shares)	371,614,758	341,474,728
Common stock, outstanding (in shares)	371,614,758	341,474,728
Series B Convertible Preferred Stock
Convertible preferred stock, par value (dollars per share)	$ 0.001	$ 0.001
Convertible preferred stock, authorized (in shares)	4,908,333	4,908,333
Convertible preferred stock, issued (in shares)	4,908,333	4,908,333
Convertible preferred stock, outstanding (in shares)	4,908,333	4,908,333
Series C Convertible Preferred Stock
Convertible preferred stock, par value (dollars per share)	$ 0.001	$ 0.001
Convertible preferred stock, authorized (in shares)	12,432,432	12,432,432
Convertible preferred stock, issued (in shares)	1,939,608	6,216,216
Convertible preferred stock, outstanding (in shares)	1,939,608	6,216,216
Undesignated preferred stock, outstanding (in shares)	1,939,608

Amount of allowance for credit loss on accounts receivable.

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