Consolidated Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$ 1,082	$ 1,391
Common Stock, par value
Common Stock, shares authorized	55,000,000	55,000,000
Common Stock, shares issued	36,677,528	36,534,464
Common Stock, shares outstanding	36,677,528	36,534,464