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Goodwill and Identifiable Assets Acquired Intangible Assets (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 305,359 | $ 296,586
Accumulated Amortization | 198,535 | 164,373
Net Carrying Amount | 106,824 | 132,213
Intangible assets not subject to amortization: |  |
Trademarks, Carrying Amount | 245,942 | 245,517
Goodwill | 894,095 | 873,513
Total |  |
Gross Carrying Amount | 551,301 | 542,103
Net Carrying Amount | 352,766 | 377,730
Customer Relationships [Member] |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | 202,588 | 196,204
Accumulated Amortization | 119,272 | 98,804
Net Carrying Amount | $ 83,316 | 97,400
Customer Relationships [Member] | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 2 months |
Customer Relationships [Member] | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 10 years |
Contractor Relations [Member] |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 71,121 | 69,721
Accumulated Amortization | 59,174 | 50,528
Net Carrying Amount | $ 11,947 | 19,193
Contractor Relations [Member] | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 2 years |
Contractor Relations [Member] | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 5 years |
Noncompete Agreements [Member] |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 11,850 | 10,861
Accumulated Amortization | 6,600 | 4,922
Net Carrying Amount | $ 5,250 | 5,939
Noncompete Agreements [Member] | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 2 years |
Noncompete Agreements [Member] | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 7 years |
Computer Software, Intangible Asset [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 6 years |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 18,900 | 18,900
Accumulated Amortization | 12,816 | 9,666
Net Carrying Amount | $ 6,084 | 9,234
Contract-Based Intangible Assets [Member] |  |
Intangible Assets [Line Items] |  |
Estimated Useful Life | 5 years |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 900 | 900
Accumulated Amortization | 673 | 453
Net Carrying Amount | $ 227 | $ 447

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- Definition Gross amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance. + References No definition available. + 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 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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- Definition Amount after accumulated impairment loss 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 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 + Details
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