Revenue Recognition - Changes in Deferred Revenue Balances (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2020	Mar. 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		(56,667)	(44,005)
Billings during period	[1]	149,692	140,549
Revenue earned for new billings during the period		(113,727)	(113,223)
Other adjustments		1,023	1,066
Gross deferred revenue, ending balance		56,920	36,081
University Group [Member] | CTU [Member]
Deferred Revenue Arrangement [Line Items]
Gross deferred revenue, beginning balance		27,845	24,250
Revenue earned from prior balances		(25,149)	(22,344)
Billings during period	[1]	103,044	97,516
Revenue earned for new billings during the period		(77,894)	(74,147)
Other adjustments		140	626
Gross deferred revenue, ending balance		27,986	25,901
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		(31,518)	(21,661)
Billings during period	[1]	46,648	43,033
Revenue earned for new billings during the period		(35,833)	(39,076)
Other adjustments		883	440
Gross deferred revenue, ending balance		$ 28,934	$ 10,180

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