Goodwill & Other Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Roll Forward]
Goodwill	$ 132,404us-gaap_GoodwillGross	$ 118,238us-gaap_GoodwillGross
Accumulated Impairment losses	(15,417)	(15,417)
Total	116,987us-gaap_Goodwill	102,821us-gaap_Goodwill
Acquisitions	12,556us-gaap_GoodwillAcquiredDuringPeriod	13,606us-gaap_GoodwillAcquiredDuringPeriod
Purchase adjustments		(79)
Foreign currency translation	(3,786)us-gaap_GoodwillTranslationAdjustments	643us-gaap_GoodwillTranslationAdjustments
Other		(4)us-gaap_GoodwillOtherChanges
Goodwill	141,174us-gaap_GoodwillGross	132,404us-gaap_GoodwillGross
Accumulated impairment losses	(15,417)	(15,417)
Total	125,757us-gaap_Goodwill	116,987us-gaap_Goodwill
Learning Solutions [Member]
Goodwill [Roll Forward]
Goodwill	62,266	48,240
Accumulated Impairment losses	(2,079)	(2,079)
Total	60,187	46,161
Acquisitions	12,556	13,606
Purchase adjustments		(196)
Foreign currency translation	(3,729)	620
Other		(4)
Goodwill	71,093	62,266
Accumulated impairment losses	(2,079)	(2,079)
Total	69,014	60,187
Professional and Technical Services [Member]
Goodwill [Roll Forward]
Goodwill	45,520	45,520
Accumulated Impairment losses	(7,830)	(7,830)
Total	37,690	37,690
Acquisitions	0	0
Purchase adjustments		0
Foreign currency translation	0	0
Other		0
Goodwill	45,520	45,520
Accumulated impairment losses	(7,830)	(7,830)
Total	37,690	37,690
Sandy Training and Marketing [Member]
Goodwill [Roll Forward]
Goodwill	6,161	6,161
Accumulated Impairment losses	(5,508)	(5,508)
Total	653	653
Acquisitions	0	0
Purchase adjustments		0
Foreign currency translation	0	0
Other		0
Goodwill	6,161	6,161
Accumulated impairment losses	(5,508)	(5,508)
Total	653	653
Performance Readiness Group [Member]
Goodwill [Roll Forward]
Goodwill	9,795	9,795
Accumulated Impairment losses	0	0
Total	9,795	9,795
Acquisitions	0	0
Purchase adjustments		0
Foreign currency translation	0	0
Other		0
Goodwill	9,795	9,795
Accumulated impairment losses	0	0
Total	9,795	9,795
Energy Services [Member]
Goodwill [Roll Forward]
Goodwill	8,662	8,522
Accumulated Impairment losses	0	0
Total	8,662	8,522
Acquisitions	0	0
Purchase adjustments		117
Foreign currency translation	(57)	23
Other		0
Goodwill	8,605	8,662
Accumulated impairment losses	0	0
Total	$ 8,605	$ 8,662

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

-URI http://asc.fasb.org/extlink&oid=14024403&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

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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=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

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