CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets
Accounts receivable, allowance for credit losses (in dollars)	$ 1,717	$ 1,510
Liabilities and stockholders' deficit
Installment payment agreement, current portion, net of discounts	$ 6	$ 6
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	48,003,724	47,674,189
Common stock, shares outstanding	48,003,724	47,674,189
Senior unsecured 2024 Notes
Liabilities and stockholders' deficit
Unamortized debt costs	$ 2,121	$ 2,121
Unamortized debt premium noncurrent	772	772
Senior secured 2026 Notes
Liabilities and stockholders' deficit
Unamortized debt costs	1,032	1,156
Unamortized debt premium noncurrent	1,371	1,536
Senior unsecured 2027 Notes
Liabilities and stockholders' deficit
Unamortized debt costs	1,283	1,283
Unamortized debt premium noncurrent	$ 2,686	$ 2,686

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

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