Segment Reporting - Summary Financial Information by Reporting Segment (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenue		$ 173,998	$ 169,126	$ 533,175	$ 516,155
Percentage of total revenue		100.00%	100.00%	100.00%	100.00%
Operating Income (Loss)		$ 37,861	$ 32,074	$ 114,440	$ 106,745
Total Assets	[1]	836,419		836,419		$ 721,517
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenue	[2],[3]	$ 262	$ 93	$ 882	$ 110
Percentage of total revenue	[2]	0.20%	0.10%	0.20%	0.00%
Operating Income (Loss)	[2]	$ (11,690)	$ (6,432)	$ (27,193)	$ (19,308)
Total Assets	[1],[2]	531,011		531,011		482,993
CTU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue	[4]	$ 104,788	$ 98,985	$ 312,645	$ 302,766
Percentage of total revenue	[4]	60.20%	58.50%	58.60%	58.70%
Operating Income (Loss)	[4]	$ 41,217	$ 32,993	$ 112,758	$ 100,688
Total Assets	[1],[4]	154,438		154,438		96,922
AIU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue	[5]	$ 68,948	$ 70,048	$ 219,648	$ 213,279
Percentage of total revenue	[5]	39.60%	41.40%	41.20%	41.30%
Operating Income (Loss)	[5]	$ 8,334	$ 5,513	$ 28,875	$ 25,365
Total Assets	[1],[5]	$ 150,970		$ 150,970		$ 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. Revenue recorded within Corporate and Other relates to miscellaneous non-student related revenue.

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

[4] CTU results of operations and total assets include the Hippo acquisition commencing on the September 10, 2021 date of acquisition and as of September 30, 2021.

[5] AIU results of operations and total assets include the DigitalCrafts acquisition commencing on the August 2, 2021 date of acquisition and as of September 30, 2021. AIU’s results of operations include Trident from the March 2, 2020 date of acquisition.