Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 10,677	$ 13,026
Preferred stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	89,462,304	85,700,953
Common stock, shares outstanding (in shares)	89,134,252	85,308,386
Treasury stock, at cost (in shares)	328,052	392,567