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Acquisitions Schedule of Intangible Assets Acquired as Part of Business Combination (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Jun. 05, 2015
Contract-Based Intangible Assets [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 5 years |
Creative Circle [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | $ 194,500
Business Acquisition, Goodwill, Expected Tax Deductible Amount |  | 358,000
Creative Circle [Member] | Trademarks [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | 66,100
Creative Circle [Member] | Contractor Relations [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | 29,500
Creative Circle [Member] | Customer Relationships [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | 90,700
Creative Circle [Member] | Noncompete Agreements [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | 7,300
Creative Circle [Member] | Contract-Based Intangible Assets [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | $ 900
Minimum [Member] | Contractor Relations [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 2 years |
Minimum [Member] | Customer Relationships [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 2 years |
Minimum [Member] | Noncompete Agreements [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 2 years |
Maximum [Member] | Contractor Relations [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 4 years |
Maximum [Member] | Customer Relationships [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 10 years |
Maximum [Member] | Noncompete Agreements [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 6 years |

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- Definition The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition Amount of intangible assets, excluding goodwill, acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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