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Goodwill and Identifiable Assets (Goodwill) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2013
Goodwill [Roll Forward] |  |
Gross goodwill, period start | $ 512,060 |
Translation adjustment | (1,632) | $ (2,366)
Gross goodwill, period end | (874,906) | 514,426
Creative Circle [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | 358,029 |
LabResource [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | 6,449 |
Apex |  |
Goodwill [Roll Forward] |  |
Gross goodwill, period start | 287,951 |
Translation adjustment | (1,363) | (1,761)
Gross goodwill, period end | (644,617) | 289,712
Apex | Creative Circle [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | 358,029 |
Apex | LabResource [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | 0 |
Oxford |  |
Goodwill [Roll Forward] |  |
Gross goodwill, period start | 224,109 |
Translation adjustment | (269) | (605)
Gross goodwill, period end | (230,289) | $ 224,714
Oxford | Creative Circle [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | 0 |
Oxford | LabResource [Member] |  |
Goodwill [Roll Forward] |  |
Goodwill, Acquired During Period | $ 6,449 |

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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + 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 + Details
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- Definition Amount before 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,h) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of increase (decrease) from foreign currency translation adjustments 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 (f) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Details
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