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Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Line Items] |  |  |
Amortization of Intangible Assets | $ 499 | $ 886 | $ 571
Western Pacific Enterprises [Member] | High Country Line Construction Inc [Member] |  |  |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Line Items] |  |  |
Goodwill, Period Increase (Decrease) | $ 200 |  |
Western Pacific Enterprises [Member] | Maximum [Member] |  |  |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Line Items] |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life | 12 years 6 months |  |
Trade Names [Member] |  |  |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Line Items] |  |  |
Estimated useful life | 15 years |  |
Customer Relationships [Member] |  |  |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Line Items] |  |  |
Estimated useful life | 12 years |  |

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- References No definition available. + Details
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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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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 Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of increase (decrease) of an asset representing future economic benefits arising 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 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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