Acquisitions (Details) - USD ($) $ in Thousands	Mar. 01, 2016	Mar. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill		$ 124,056	$ 121,975
Jencal Training [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 2,700
Goodwill	1,700
Maximum contingent consideration due in 2014		429
Maximum contingent consideration due Total	400
Original range of potential undiscounted payments minimum		0
Original range of potential undiscounted payments maximum		$ 429
Finite-Lived Intangible Assets [Member] | Jencal Training [Member]
Business Acquisition [Line Items]
Business Acquisition Purchase Price Allocation And Amortizable Intangible Assets	$ 1,400
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years