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Acquisitions Acquisitions (Schedule of Intangible Assets Acquired as Part of Business Combination) (Details) - USD ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2015 | Jun. 05, 2015 | Apr. 14, 2015 | Dec. 05, 2013
Contract-Based Intangible Assets [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 5 years |  |  |
Computer Software, Intangible Asset [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquired Finite Lived Intangible Assets Average Useful Life | 6 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 |  | $ 194,500,000 |  |
Business Acquisition, Goodwill, Expected Tax Deductible Amount |  | 358,029,000 |  |
Creative Circle [Member] | Computer Software, Intangible Asset [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  | 0 |  |
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 |  | 66,100,000 |  |
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 |  | 29,500,000 |  |
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 |  | 90,700,000 |  |
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 |  | 7,300,000 |  |
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 |  | $ 900,000 |  |
LabResource [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  | $ 7,528,000 |
LabResource [Member] | Computer Software, Intangible Asset [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  | 0 |
LabResource [Member] | Trademarks [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  | 1,140,000 |
LabResource [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 |  |  | 947,000 |
LabResource [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 |  |  | 5,421,000 |
LabResource [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 |  |  | 20,000 |
LabResource [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 |  |  | $ 0 |
CyberCoders [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  |  | $ 37,860,000
Business Acquisition, Goodwill, Expected Tax Deductible Amount |  |  |  | 10,300,000
CyberCoders [Member] | Computer Software, Intangible Asset [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  |  | 18,900,000
CyberCoders [Member] | Trademarks [Member] |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill |  |  |  | 13,300,000
CyberCoders [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 |  |  |  | 4,000,000
CyberCoders [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 |  |  |  | 860,000
CyberCoders [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 |  |  |  | 800,000
CyberCoders [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 |  |  |  | $ 0
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 | 3 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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