Interim Condensed Consolidated Statements of Income (Unaudited) - USD ($)
shares in Thousands, $ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Net sales:        
Net sales $ 216,766 $ 231,614 $ 639,226 $ 655,146
Cost of sales 162,055 174,105 482,060 501,435
Gross profit 54,711 57,509 157,166 153,711
Selling, general and administrative expenses 33,699 33,939 101,824 101,578
Income from operations 21,012 23,570 55,342 52,133
Interest expense (1,405) (1,671) (4,334) (5,142)
Interest income 43 27 161 120
Other income (expense), net 127 895 (253) 2,243
Income before income taxes 19,777 22,821 50,916 49,354
Provision for income taxes 6,541 8,065 18,459 17,529
Net Income $ 13,236 $ 14,756 $ 32,457 $ 31,825
Net income per common share:        
Basic (in dollars per share) $ 1.15 $ 1.30 $ 2.84 $ 2.81
Diluted (in dollars per share) $ 1.14 $ 1.28 $ 2.81 $ 2.77
Average common shares:        
Basic (in shares) 11,460 11,380 11,424 11,337
Diluted (in shares) 11,595 11,496 11,551 11,477
Dividends declared (in dollars per share) $ 0.09000 $ 0.08000 $ 0.27000 $ 0.24000
Industrial        
Net sales:        
Net sales $ 121,205 $ 127,385 $ 361,629 $ 362,818
Income from operations 9,318 11,741 30,016 31,178
Agricultural        
Net sales:        
Net sales 56,443 58,919 156,950 160,357
Income from operations 7,928 7,778 16,735 12,292
European        
Net sales:        
Net sales 39,118 45,310 120,647 131,971
Income from operations $ 3,766 $ 4,051 $ 8,591 $ 8,663