Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net sales:
Net sales:	$ 879,577	$ 839,055	$ 682,090
Cost of sales	677,129	649,827	523,580
Gross profit	202,448	189,228	158,510
Selling, general and administrative expenses	135,920	126,564	107,773
Income from operations	66,528	62,664	50,737
Interest expense	(6,724)	(4,037)	(1,161)
Interest income	189	211	186
Other income (expense), net	6,874	1,767	1,626
Income before income taxes	66,867	60,605	51,388
Provision for income taxes	23,658	19,454	15,294
Net income	$ 43,209	$ 41,151	$ 36,094
Net income per common share:
Basic (in dollars per share)	$ 3.81	$ 3.47	$ 3.00
Diluted (in dollars per share)	$ 3.76	$ 3.42	$ 2.96
Average common shares:
Basic (in shares)	11,349	11,875	12,050
Diluted (in shares)	11,482	12,039	12,212
Industrial
Net sales:
Net sales:	$ 498,761	$ 436,018	$ 297,857
Income from operations	42,194	39,377	25,743
Agricultural
Net sales:
Net sales:	208,257	214,326	219,354
Income from operations	17,295	11,714	17,880
European
Net sales:
Net sales:	172,559	188,711	164,879
Income from operations	$ 7,039	$ 11,573	$ 7,114