Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1,285	$ 4,183
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	30,000,000	30,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	187,500,000	187,500,000
Common stock, shares issued (in shares)	127,317,890	126,153,173
Common stock, shares outstanding (in shares)	122,465,518	121,318,175
Treasury stock, shares (in shares)	4,852,372	4,834,998