Revenue and Segment Information - Revenue, Income, Goodwill and Identifiable Assets by Location (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 285,186	$ 257,125	$ 547,120	$ 495,212
Income from Operations	29,349	26,786	51,955	48,147
Goodwill	93,134		93,134		$ 83,243
Total Identifiable Assets	866,579		866,579		721,633
Industrial
Segment Reporting Information [Line Items]
Net Sales	168,000	150,031	326,425	282,198
Income from Operations	20,172	16,165	36,644	27,965
Goodwill	61,433		61,433		61,107
Total Identifiable Assets	465,860		465,860		421,539
Agricultural
Segment Reporting Information [Line Items]
Net Sales	55,159	59,071	108,332	117,718
Income from Operations	4,234	6,186	6,406	11,439
Goodwill	6,276		6,276		6,230
Total Identifiable Assets	177,673		177,673		162,548
European
Segment Reporting Information [Line Items]
Net Sales	62,027	48,023	112,363	95,296
Income from Operations	4,943	$ 4,435	8,905	$ 8,743
Goodwill	25,425		25,425		15,906
Total Identifiable Assets	$ 223,046		$ 223,046		$ 137,546

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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