Revenue Recognition - Changes in Deferred Revenue Balances (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Deferred Revenue Arrangement [Line Items]
Gross deferred revenue, beginning balance		$ 63,204	$ 51,694
Business acquisition, beginning balance		13,395
Revenue earned from prior balances		(65,581)	(44,113)
Billings during period	[1]	694,681	635,826
Revenue earned for new billings during the period		(618,997)	(580,943)
Other adjustments		(1,300)	740
Gross deferred revenue, ending balance		85,402	63,204
University Group [Member] | CTU [Member]
Deferred Revenue Arrangement [Line Items]
Gross deferred revenue, beginning balance		27,845	24,250
Revenue earned from prior balances		(25,179)	(22,289)
Billings during period	[1]	404,930	392,818
Revenue earned for new billings during the period		(378,161)	(367,563)
Other adjustments		(913)	629
Gross deferred revenue, ending balance		28,522	27,845
University Group [Member] | AIU [Member]
Deferred Revenue Arrangement [Line Items]
Gross deferred revenue, beginning balance		35,359	27,444
Business acquisition, beginning balance		13,395
Revenue earned from prior balances		(40,402)	(21,824)
Billings during period	[1]	289,751	243,008
Revenue earned for new billings during the period		(240,836)	(213,380)
Other adjustments		(387)	111
Gross deferred revenue, ending balance		$ 56,880	$ 35,359

[1] Billings during period includes adjustments for prior billings.