Intangible Assets (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 127,772
Acquisitions	8,301
Foreign currency translation	2,320
Ending Balance	138,393
Learning Solutions
Goodwill [Roll Forward]
Beginning Balance	49,079
Acquisitions	3,156
Foreign currency translation	1,859
Ending Balance	54,094
Professional and Technical Services
Goodwill [Roll Forward]
Beginning Balance	42,364
Acquisitions	0
Foreign currency translation	394
Ending Balance	42,758
Sandy Training and Marketing
Goodwill [Roll Forward]
Beginning Balance	653
Acquisitions	0
Foreign currency translation	0
Ending Balance	653
Performance Readiness Group
Goodwill [Roll Forward]
Beginning Balance	35,676
Acquisitions	5,145
Foreign currency translation	67
Ending Balance	$ 40,888