Goodwill & Other Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Oct. 02, 2012
Goodwill	$ 108,755	$ 88,413
Accumulated impairment losses	(15,417)	(15,417)
Total	93,338	72,996
Acquisitions	8,566	20,711	90
Foreign currency translation	925	(277)
Other	(8)	(92)
Goodwill	118,238	108,755
Accumulated impairment losses	(15,417)	(15,417)
Total	102,821	93,338
Learning Solutions [Member]
Goodwill	47,149	41,115
Accumulated impairment losses	(2,079)	(2,079)
Total	45,070	39,036
Acquisitions	8,226	6,440
Foreign currency translation	903	(322)
Other	0	(84)
Goodwill	56,278	47,149
Accumulated impairment losses	(2,079)	(2,079)
Total	54,199	45,070
Professional and Technical Services [Member]
Goodwill	37,480	33,620
Accumulated impairment losses	(7,830)	(7,830)
Total	29,650	25,790
Acquisitions	0	3,823
Foreign currency translation	10	45
Other	(8)	(8)
Goodwill	37,482	37,480
Accumulated impairment losses	(7,830)	(7,830)
Total	29,652	29,650
Sandy Training and Marketing [Member]
Goodwill	6,161	5,508
Accumulated impairment losses	(5,508)	(5,508)
Total	653	0
Acquisitions	0	653
Foreign currency translation	0	0
Other	0	0
Goodwill	6,161	6,161
Accumulated impairment losses	(5,508)	(5,508)
Total	653	653
Energy Services [Member]
Goodwill	8,170	8,170
Accumulated impairment losses	0	0
Total	8,170	8,170
Acquisitions	340	0
Foreign currency translation	12	0
Other	0	0
Goodwill	8,522	8,170
Accumulated impairment losses	0	0
Total	8,522	8,170
Performance Readiness Group [Member]
Goodwill	9,795	0
Accumulated impairment losses	0	0
Total	9,795	0
Acquisitions	0	9,795
Foreign currency translation	0	0
Other	0	0
Goodwill	9,795	9,795
Accumulated impairment losses	0	0
Total	$ 9,795	$ 9,795