Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts, accounts receivable	$ 2,031	$ 1,899
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	55,027,081	54,903,824
Common stock, shares outstanding	27,528,786	28,142,519
Treasury stock, shares	27,498,295	26,761,305