Segment Reporting - Summary Financial Information by Reporting Segment (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenue		$ 183,638	$ 170,994
Percentage of total revenue		100.00%	100.00%
Operating Income (Loss)		$ 40,617	$ 37,303
Total Assets	[1]	750,365		$ 721,517
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenue	[2],[3]	339	10
Operating Income (Loss)	[2]	(6,849)	(6,692)
Total Assets	[1],[2]	518,167		482,993
CTU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue		$ 105,822	$ 103,588
Percentage of total revenue		57.60%	60.60%
Operating Income (Loss)		$ 36,143	$ 34,619
Total Assets	[1]	102,237		96,922
AIU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue	[4]	$ 77,477	$ 67,396
Percentage of total revenue	[4]	42.20%	39.40%
Operating Income (Loss)	[4]	$ 11,323	$ 9,376
Total Assets	[1]	$ 129,961		$ 141,602

[1] Total assets do not include intercompany receivable or payable activity between institutions and corporate and investments in subsidiaries.

[2] Corporate and Other includes results of operations and total assets for closed campuses.

[3] Revenue recorded within Corporate and Other relates to miscellaneous non-student related revenue.

[4] AIU’s revenue and operating income for the quarter ended March 31, 2020, include results of operations related to Trident from the March 2, 2020 date of acquisition and therefore do not reflect a full quarter of activity for Trident.