Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	$ 102,821
Acquisitions	13,558
Purchase accounting adjustments	(78)
Foreign currency translation	406
Balance as of September 30, 2013	116,707
Learning Solutions [Member]
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	46,161
Acquisitions	13,558
Purchase accounting adjustments	(195)
Foreign currency translation	391
Balance as of September 30, 2013	59,915
Professional and Technical Services [Member]
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	37,690
Acquisitions	0
Purchase accounting adjustments	0
Foreign currency translation	0
Balance as of September 30, 2013	37,690
Sandy Training and Marketing [Member]
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	653
Acquisitions	0
Purchase accounting adjustments	0
Foreign currency translation	0
Balance as of September 30, 2013	653
Performance Readiness Group [Member]
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	9,795
Acquisitions	0
Purchase accounting adjustments	0
Foreign currency translation	0
Balance as of September 30, 2013	9,795
Energy Services [Member]
Finite-Lived Intangible Assets [Line Items]
Balance as of December 31, 2012	8,522
Acquisitions	0
Purchase accounting adjustments	117
Foreign currency translation	15
Balance as of September 30, 2013	$ 8,654