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Goodwill (Schedule of Goodwill) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Goodwill [Roll Forward] |  |  |
Goodwill, balance at the beginning of the period | $ 74,825 | $ 75,509 | $ 75,691
Translation adjustment | 2,195 | (684) | (3,181)
Goodwill acquired | 7,741 |  | 2,999
Goodwill, balance at the end of the period | 84,761 | 74,825 | 75,509
Industrial |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, balance at the beginning of the period | 56,447 | 56,293 | 57,320
Translation adjustment | 389 | 154 | (1,027)
Goodwill acquired | 4,846 |  | 0
Goodwill, balance at the end of the period | 61,682 | 56,447 | 56,293
Agricultural |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, balance at the beginning of the period | 3,489 | 2,984 | 695
Translation adjustment | (27) | 505 | (710)
Goodwill acquired | 2,895 |  | 2,999
Goodwill, balance at the end of the period | 6,357 | 3,489 | 2,984
European |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, balance at the beginning of the period | 14,889 | 16,232 | 17,676
Translation adjustment | 1,833 | (1,343) | (1,444)
Goodwill acquired | 0 |  | 0
Goodwill, balance at the end of the period | $ 16,722 | $ 14,889 | $ 16,232

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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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