Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Allowance for doubtful accounts	$ 2,511	$ 2,080
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0667	$ 0.0667
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	32,447,415	32,405,796
Common stock, shares outstanding (in shares)	32,316,842	32,201,917
Treasury stock (in shares)	130,573	203,879