UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Allowance for doubtful accounts	$ 2,108	$ 2,061
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	52,806,000	53,092,000
Common stock, shares outstanding (in shares)	52,145,000	52,431,000
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1.000	1.000
Preferred stock, shares outstanding (in shares)	1.000	1.000
Series B Convertible Stock
Series B convertible preferred stock par value (in dollars per share)	$ 0.0001	$ 0.0001
Series B convertible preferred stock, shares authorized (in shares)	150,000	150,000
Series B convertible preferred stock, shares issued (in shares)	150,000	150,000
Series B convertible preferred stock, shares outstanding (in shares)	145,000	150,000
Treasury Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Treasury stock (in shares)	661,000	661,000