Changes in the Company's carrying value of goodwill by reporting segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Goodwill, Gross, Period Start	$ 108,041	$ 96,251
Accumulated Impairment Loss	(43,581)	(62,247)	$ (45,621)
Additions	0	16,445
Impairment	0	(21,034)
Translation and other adjustments	(366)	(247)
Goodwill, Gross, End of Period	89,009	108,041
Enterprise Talent [Member]
Goodwill [Roll Forward]
Goodwill, Gross, Period Start	40,134	44,298
Accumulated Impairment Loss	(16,868)	(34,511)	(27,904)
Additions	0	0
Impairment	0	(10,654)
Translation and other adjustments	0	(117)
Goodwill, Gross, End of Period	22,491	40,134
Specialty Talent and Technology Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Gross, Period Start	16,445	0
Accumulated Impairment Loss	0	0	0
Additions	0	16,445
Impairment	0	0
Translation and other adjustments	0	0
Goodwill, Gross, End of Period	16,445	16,445
Engineering Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Gross, Period Start	35,713	35,713
Accumulated Impairment Loss	(21,431)	(21,431)	(11,051)
Additions	0	0
Impairment	0	(10,380)
Translation and other adjustments	0	0
Goodwill, Gross, End of Period	35,713	35,713
MRI [Member]
Goodwill [Roll Forward]
Goodwill, Gross, Period Start	15,749	16,240
Accumulated Impairment Loss	(5,282)	(6,305)	$ (6,666)
Additions	0	0
Translation and other adjustments	(366)	(130)
Goodwill, Gross, End of Period	$ 14,360	$ 15,749

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.

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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.

+ References

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Amount of accumulated impairment loss for 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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- Definition

Amount of loss from the write-down of an asset representing the 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 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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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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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting 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 (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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