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Goodwill and Definite and Indefinite-lived Intangible Assets (Definite and Indefinite Lived Intangible Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Definite intangible assets | $ 58,350 |  | $ 58,350 |  | $ 58,912
Less accumulated amortization | (13,214) |  | (13,214) |  | (11,540)
Total net | 45,136 |  | 45,136 |  | 47,372
Total Intangible Assets | 50,636 |  | 50,636 |  | 52,872
Amortization of intangibles | 875 | $ 777 | 1,756 | $ 1,554 |
Intangible assets, net | 50,636 |  | $ 50,636 |  | 52,872
Total assets | Indefinite-lived and Finite-Lived Intangible Assets |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Percentage of total assets |  |  | 7.00% |  |
Trade names and trademarks |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Indefinite intangible assets | 5,500 |  | $ 5,500 |  | 5,500
Trade names and trademarks |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Estimated Useful Lives |  |  | 25 years |  |
Definite intangible assets | 23,985 |  | $ 23,985 |  | 24,276
Customer and dealer relationships |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Definite intangible assets | 32,401 |  | $ 32,401 |  | 32,654
Customer and dealer relationships | Minimum |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Estimated Useful Lives |  |  | 10 years |  |
Customer and dealer relationships | Maximum |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Estimated Useful Lives |  |  | 14 years |  |
Patents and drawings |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Definite intangible assets | $ 1,964 |  | $ 1,964 |  | $ 1,982
Patents and drawings | Minimum |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Estimated Useful Lives |  |  | 3 years |  |
Patents and drawings | Maximum |  |  |  |  |
Schedule of Acquired Indefinite-lived and Finite Intangible Assets by major class [Line Items] |  |  |  |  |
Estimated Useful Lives |  |  | 12 years |  |

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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