Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 6,788	$ 3,116	$ 11,766	$ 5,918
Foreign currency translation adjustment	672	(1,025)	1,743	(818)
Deferred gain on available for sale securities	238	99	464	164
Current period cash flow hedging activity, net of $283 and $369 tax benefit in the three and six months ended June 30, 2017, and $308 and $988 tax benefit in the three and six months ended June 30, 2016, respectively.	(620)	(514)	(859)	(1,881)
Reclassification of hedging activities into earnings, net of $77 and $89 tax benefit in the three and six months ended June 30, 2017, respectively, and $44 and $105 tax benefit in the three and six months ended June 30, 2016, respectively.	134	33	140	108
Reclassification of pension and postretirement adjustments into earnings, net of $38 and $88 tax benefit in the three and six months ended June 30, 2017, respectively, and $84 and $183 tax benefit in the three and six months ended June 30, 2016, respectively.	148	153	324	302
Total other comprehensive income (loss)	572	(1,254)	1,812	(2,125)
Comprehensive income	$ 7,360	$ 1,862	$ 13,578	$ 3,793