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Goodwill And Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Schedule of Goodwill and Intangible Assets [Line Items] |  |  |
Amortization of intangible assets | $ 12,135 | $ 14,427 | $ 10,423
Customer Relationships [Member] |  |  |
Schedule of Goodwill and Intangible Assets [Line Items] |  |  |
Weighted-average remaining lives of intangible assets | 10 years 9 months 18 days |  |
Trade Name [Member] |  |  |
Schedule of Goodwill and Intangible Assets [Line Items] |  |  |
Weighted-average remaining lives of intangible assets | 10 years 7 months 6 days |  |
Non-Compete Agreements [Member] |  |  |
Schedule of Goodwill and Intangible Assets [Line Items] |  |  |
Weighted-average remaining lives of intangible assets | 9 years 7 months 6 days |  |

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- Definition Schedule of goodwill and intangible assets. + References No definition available. + 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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- Details
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