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.

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=64834752&loc=SL49117168-202975

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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

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Goodwill and Identifiable Assets (Goodwill) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Gross goodwill	$ 874,919	$ 874,906	$ 512,060
Goodwill	874,919	874,906
Translation adjustment	13	(1,632)
Apex
Goodwill [Roll Forward]
Gross goodwill	644,537	644,617	287,951
Translation adjustment	(80)	(1,363)
Oxford
Goodwill [Roll Forward]
Gross goodwill	230,382	230,289	$ 224,109
Translation adjustment	$ 93	(269)
Creative Circle [Member]
Goodwill [Roll Forward]
Goodwill, Acquired During Period		358,029
Creative Circle [Member] \| Apex
Goodwill [Roll Forward]
Goodwill, Acquired During Period		358,029
Creative Circle [Member] \| Oxford
Goodwill [Roll Forward]
Goodwill, Acquired During Period		0
LabResource [Member]
Goodwill [Roll Forward]
Goodwill, Acquired During Period		6,449
LabResource [Member] \| Apex
Goodwill [Roll Forward]
Goodwill, Acquired During Period		0
LabResource [Member] \| Oxford
Goodwill [Roll Forward]
Goodwill, Acquired During Period		$ 6,449