Debt (Details 1) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015	Jan. 31, 2009
Debt Instrument [Line Items]
Other indebtedness		$ 1,479	$ 1,204
Total Debt		491,847	399,800
Less: current portion		(6,128)	0
Total Long-Term Debt		485,719	399,800
7.25% Unsecured Notes due February 1, 2019 [Member]
Debt Instrument [Line Items]
Unsecured notes	[1]	$ 399,052	$ 398,596
Interest rate of debt instrument		7.25%	7.25%	7.25%
Kaplan Four Year Credit Agreement Dated July 14, 2016 [Member]
Debt Instrument [Line Items]
UK Credit Facility	[2]	$ 91,316	$ 0

[1] The carrying value is net of $0.1 million of unamortized debt issuance costs as of December 31, 2016 and 2015, respectively.

[2] The carrying value is net of $0.5 million of unamortized debt issuance costs as of December 31, 2016.