Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Allowance for doubtful accounts	$ 5,197	$ 5,483
Treasury shares (in shares)	68,658
Class A Common Stock
Common stock, par value (USD per share)	$ 0.0000001	$ 0.0000001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	15,750,097	12,995,080
Common stock, shares outstanding (in shares)	15,681,439	12,995,080
Class B Common Stock
Common stock, par value (USD per share)	$ 0.0000001	$ 0.0000001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	1,926,848	3,560,604
Common stock, shares outstanding (in shares)	1,926,489	3,560,604
Term Loan Due 2026
Debt issuance costs	$ 5,007
6.75% Senior Notes
Debt issuance costs	$ 6,938

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

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