Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Allowances for accounts receivable
Allowances for accounts receivable	$ 6,320	$ 3,486
Convertible preferred stock
Convertible preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized (in shares)	100,000,000	314,930,070
Convertible preferred stock, shares issued (in shares)	0	65,428,088
Convertible preferred stock, shares outstanding (in shares)	0	65,428,088
Convertible preferred stock, aggregate liquidation preference	$ 0	$ 106,369
Common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,000,000,000	417,000,000
Common stock, shares issued (in shares)	84,188,202	5,155,407
Common stock, shares outstanding (in shares)	10,046,705	5,155,407
Treasury stock
Treasury stock, shares outstanding (in shares)	615,980	589,320

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