Debt (Details 1) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Other indebtedness		$ 1,486	$ 1,204
Total Debt		497,408	399,800
Less: current portion		(6,498)	0
Total Long-Term Debt		490,910	399,800
7.25% Unsecured Notes due February 1, 2019 [Member]
Debt Instrument [Line Items]
Unsecured notes	[1]	$ 398,938	$ 398,596
Debt Instrument, Interest Rate, Stated Percentage		7.25%	7.25%
Unamortized debt issuance costs		$ 100	$ 100
Kaplan Four-Year Credit Agreement dated July 14, 2016 [Member]
Debt Instrument [Line Items]
UK Credit Facility	[2]	96,984	$ 0
Unamortized debt issuance costs		$ 600

[1] The carrying value is net of $0.1 million of unamortized debt issuance costs as of September 30, 2016 and December 31, 2015, respectively.

[2] The carrying value is net of $0.6 million of unamortized debt issuance costs as of September 30, 2016