CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2020	May 15, 2020	Dec. 31, 2019
Allowance for doubtful accounts	$ 2,399,000		$ 2,208,000
Stated interest rate		1.00%
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01
Common stock, shares authorized (in shares)	100,000,000		100,000,000
Common stock, shares issued (in shares)	21,754,223		5,385,043
Common stock, shares outstanding (in shares)	21,754,223		5,385,043
Convertible Notes Payable
Principal	$ 181,580,000		$ 213,959,000
Convertible Notes Payable \| 2023 Senior Notes
Stated interest rate	4.75%		4.75%
Principal	$ 0		$ 66,090,000
Convertible Notes Payable \| 2023 Series B Convertible Notes
Principal	0		34,405,000
Convertible Notes Payable \| 2023 Series C Convertible Notes
Principal	50,323,000		0
Convertible Notes Payable \| 2023 Series D Convertible Notes
Principal	3,352,000		0
Convertible Notes Payable \| Senior Notes, due February 2023
Principal	102,905,000		88,464,000
Revolving Credit Facility \| Line of Credit
Principal	$ 25,000,000		$ 25,000,000

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

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