CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets
Accounts receivable, allowance for credit losses (in dollars)	$ 2,204	$ 1,771
Liabilities and stockholders' equity
Installment payment agreement, current portion, net of discounts	$ 245	$ 350
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	47,284,336	46,840,434
Common stock, shares outstanding	47,284,336	46,840,434
Senior secured 2022 notes
Liabilities and stockholders' equity
Unamortized debt costs	$ 1,267	$ 1,897
Unamortized debt premium	656	985
Senior unsecured 2024 notes
Liabilities and stockholders' equity
Unamortized debt costs	3,166	1,410
Unamortized debt premium	1,164	$ 0
Senior unsecured 2021 notes
Liabilities and stockholders' equity
Unamortized debt costs	$ 857

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

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