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Goodwill and Identifiable Assets (Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Intangible Assets [Line Items] |  |  |
Amortization of intangible assets | $ 7,601 | $ 8,464 |
Intangible assets subject to amortization: |  |  |
Gross Carrying Amount | 305,708 |  | $ 305,359
Accumulated Amortization | 206,315 |  | 198,535
Net Carrying Amount | 99,393 |  | 106,824
Intangible assets not subject to amortization: |  |  |
Trademarks, Carrying Amount | 245,977 |  | 245,942
Goodwill, Carrying Amount | 894,888 |  | 894,095
Intangible Assets, Gross (Excluding Goodwill) | 551,685 |  | 551,301
Total |  |  |
Intangible Assets, Net (Excluding Goodwill) | 345,370 |  | 352,766
Customer relations |  |  |
Intangible assets subject to amortization: |  |  |
Gross Carrying Amount | 202,800 |  | 202,588
Accumulated Amortization | 123,802 |  | 119,272
Net Carrying Amount | $ 78,998 |  | 83,316
Customer relations | Minimum [Member] |  |  |
Intangible Assets [Line Items] |  |  |
Estimated Useful Life | 2 years |  |
Customer relations | Maximum [Member] |  |  |
Intangible Assets [Line Items] |  |  |
Estimated Useful Life | 10 years |  |
Contractor Relations [Member] |  |  |
Intangible assets subject to amortization: |  |  |
Gross Carrying Amount | $ 71,200 |  | 71,121
Accumulated Amortization | 61,191 |  | 59,174
Net Carrying Amount | $ 10,009 |  | 11,947
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 |  |
Non-compete agreements |  |  |
Intangible assets subject to amortization: |  |  |
Gross Carrying Amount | $ 11,908 |  | 11,850
Accumulated Amortization | 7,013 |  | 6,600
Net Carrying Amount | $ 4,895 |  | 5,250
Non-compete agreements | Minimum [Member] |  |  |
Intangible Assets [Line Items] |  |  |
Estimated Useful Life | 2 years |  |
Non-compete agreements | 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 | 13,603 |  | 12,816
Net Carrying Amount | $ 5,297 |  | 6,084
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 | 706 |  | 673
Net Carrying Amount | $ 194 |  | $ 227

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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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- Definition Amount before 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 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 Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit. + 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 (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph ((a)(1),(b)) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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