Consolidated Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$ 1,040	$ 851
Common Stock, par value
Common Stock, shares authorized	55,000,000	55,000,000
Common Stock, shares issued	32,741,826	33,856,629
Common Stock, shares outstanding	32,741,826	33,856,629