CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED BALANCE SHEETS
Allowance for doubtful accounts receivable, current (in dollars)	$ 8,209	$ 6,387
Common stock voting, par value (in dollars per share)	$ 0.0025	$ 0.0025
Common stock voting, shares authorized (in shares)	900,000,000	900,000,000
Common stock voting, shares issued (in shares)	266,618,566	266,072,787
Common stock voting, shares outstanding (in shares)	210,914,264	214,502,639
Treasury stock, shares (in shares)	55,704,302	51,570,148

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

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