Acquisitions (Details)	3 Months Ended	6 Months Ended			1 Months Ended	3 Months Ended						1 Months Ended		1 Months Ended		1 Months Ended		3 Months Ended	6 Months Ended
	Feb. 28, 2015 USD ($)	Feb. 28, 2015 USD ($)	Feb. 28, 2014 USD ($)	Aug. 31, 2014 USD ($)	Dec. 31, 2014 Faculdade da Educacional da Lapa [Member] USD ($)	Feb. 28, 2015 Faculdade da Educacional da Lapa [Member] USD ($)	Feb. 28, 2015 Faculdade da Educacional da Lapa [Member] BRL	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] USD ($)	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] BRL	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] Trademarks [Member] USD ($)	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] Accreditation [Member] USD ($)	Dec. 31, 2014 Faculdade da Educacional da Lapa [Member] Curriculum [Member]	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] Curriculum [Member] USD ($)	Dec. 31, 2014 Faculdade da Educacional da Lapa [Member] Other [Member]	Dec. 04, 2014 Faculdade da Educacional da Lapa [Member] Other [Member] USD ($)	Dec. 31, 2013 Open Colleges [Member] USD ($)	Dec. 31, 2013 Open Colleges [Member] AUD	Feb. 28, 2014 Open Colleges [Member] USD ($)	Feb. 28, 2015 Open Colleges [Member] USD ($)	Feb. 28, 2014 Open Colleges [Member] USD ($)	Dec. 20, 2013 Open Colleges [Member] USD ($)
Purchase price allocation [Line Items]
Percentage of shares acquired								75.00%	75.00%												70.00%
Initial cash payment						$ 28,851,000	73,800,000									$ 98,100,000	110,300,000
Contingent consideration maximum								13,300,000	34,000,000
Transaction costs								1,200,000
Net working capital deficit																					(10,979,000)
Property and equipment																					2,684,000
Indefinite-lived intangibles										9,223,000	5,940,000
Finite-lived intangibles													1,212,000		4,182,000						60,575,000
Finite-lived intangible assets, useful life												4 years		4 years
Goodwill	248,632,000	248,632,000		259,901,000				14,538,000													127,656,000
Other assets								2,877,000
Liabilities								(13,369,000)													(33,000,000)
Deferred taxes, net																					(9,279,000)
Total assets acquired and liabilities assumed								32,288,000													170,657,000
Fair value of redeemable noncontrolling interests								(3,437,000)													(51,197,000)
Fair value of contingent consideration	0	0														(21,371,000)		(21,371,000)	(21,371,000)	(21,371,000)
Fair value of consideration transferred								28,851,000													119,460,000
Cash and cash equivalents								(7,685,000)													(3,152,000)
Cash paid for acquisition, net of cash acquired		$ 21,166,000	$ 94,937,000		$ 21,166,000											$ 94,937,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					4 years