Discontinued Operations and Assets Held for Sale - Schedule of carrying amounts of the major classes of assets and liabilities classified as held for sale (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Subtotal: assets of Discontinued Operations	$ 1,337,831	$ 1,549,340
Total liabilities held for sale	662,684	857,316
Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	214,934	197,898
Receivables, net	38,588	83,045
Property and equipment, net	667,527	830,408
Goodwill	131,329	159,042
Tradenames	124,932	156,746
Other assets	99,566	122,201
Subtotal: assets of Discontinued Operations	1,276,876	1,549,340
Deferred revenue and student deposits	115,969	223,163
Long-term debt, including current portion	278,074	319,473
Other liabilities	253,397	314,680
Total liabilities held for sale	647,440	857,316
UniNorte Brazil | Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Receivables, net	6,983	0
Property and equipment, net	16,726	0
Goodwill	15,165	0
Tradenames	8,146	0
Other assets	13,935	0
Subtotal: assets of Discontinued Operations	60,955	0
Deferred revenue and student deposits	469	0
Long-term debt, including current portion	5,370	0
Other liabilities	9,405	0
Total liabilities held for sale	$ 15,244	$ 0