Interim Condensed Consolidated Statements of Stockholders' Equity - 6 months ended Jun. 30, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Balance at Dec. 31, 2015	$ 360,469	$ 1,139	$ 96,778	$ (426)	$ 299,057	$ (36,079)
Balance (shares) at Dec. 31, 2015		11,350
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	19,221				19,221
Translation adjustment	(3,581)					(3,581)
Net actuarial gain arising during period	336					336
Tax effect of non-qualified stock options	141		141
Stock-based compensation	724		724
Exercise of stock options	998	$ 6	992
Exercise of stock options (shares)		56
Repurchased shares	(19)		(19)
Dividends paid ($.18 per share)	(2,051)				(2,051)
Balance at Jun. 30, 2016	$ 376,238	$ 1,145	$ 98,616	$ (426)	$ 316,227	$ (39,324)
Balance (shares) at Jun. 30, 2016		11,406