Legal and Regulatory Matters - Turkish Regulation and Internal Investigation (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Loss Contingencies [Line Items]
Assets	$ 7,910,591		$ 7,062,470
Liabilities	6,364,401		6,041,245
Revenues	855,933	$ 906,534
Operating loss	(62,866)	$ (11,157)
Variable Interest Entity, Primary Beneficiary
Loss Contingencies [Line Items]
Assets	1,433,048		1,309,113
Liabilities	550,340		424,297
Variable Interest Entity, Primary Beneficiary | Istanbul Bilgi University
Loss Contingencies [Line Items]
Required reimbursement, other activities			8,000
Assets	95,000		83,000
Liabilities	71,000		63,000
Revenues			106,000
Operating loss			26,000
Depreciation and amortization			6,000
Variable Interest Entity, Primary Beneficiary | Istanbul Bilgi University | Consolidation Eliminations
Loss Contingencies [Line Items]
Due to related party	$ 23,000		19,000
Variable Interest Entity, Primary Beneficiary | Management, Operational And Student Services, And Intellectual Property | Subsidiary of Common Parent | Istanbul Bilgi University
Loss Contingencies [Line Items]
Required reimbursement from related party			$ 29,000