Consolidated Statement of Shareholders' Equity - 3 months ended Mar. 31, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Balance, shares at Dec. 31, 2015		31,779				484
Balance, value at Dec. 31, 2015	$ 410,086	$ 317	$ 253,458	$ 178,073	$ (15,416)	$ (6,346)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,493			6,493
Foreign currency translation adjustment	3,078				3,078
Adjustment to retirement benefit liability, net of taxes of $1	(1)				(1)
Adjustment to post employment health care benefit liability, net of taxes of $22	38				38
Reclassification of loss on cash flow hedges, net of tax of $82	0
Stock compensation expense	1,348		1,348
Excess tax benefit from stock compensation	187		187
Stock options exercised, shares		8
Stock options exercised	133		133
Issuance of restricted stock, shares		(3)
Issuance of restricted stock	0	$ 0	0
Net settlement of restricted stock units, shares		43				16
Net settlement of restricted stock units	(414)	$ 1	(1)			$ (414)
Balance, shares at Mar. 31, 2016		31,827				500
Balance, value at Mar. 31, 2016	$ 420,948	$ 318	$ 255,125	$ 184,566	$ (12,301)	$ (6,760)