Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 11,581	$ 10,677
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common sock, shares authorized (shares)	300,000,000	300,000,000
Common stock, shares issued (shares)	90,343,931	89,462,304
Common stock, shares outstanding (shares)	90,041,200	89,134,252
Treasury stock (shares)	302,731	328,052