Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Allowance for doubtful accounts	$ 1,354	$ 610
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)	32,401,586	32,256,915
Common stock, shares outstanding (in shares)	32,169,087	32,256,209
Treasury stock (in shares)	232,499	706