Segment Reporting - Summary Financial Information by Reporting Segment (Detail) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019		Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenue		$ 169,126		$ 154,959	$ 516,155		$ 469,253
Percentage of total revenue		100.00%		100.00%	100.00%		100.00%
Operating Income (Loss)		$ 32,074		$ 24,294	$ 106,745		$ 54,449
Total Assets	[1]	683,751			683,751				$ 599,146
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Total Assets	[1]	81			81				81
University Group [Member]
Segment Reporting Information [Line Items]
Revenue		$ 169,033		$ 154,945	$ 516,045		$ 469,209
Percentage of total revenue		99.90%		100.00%	100.00%		100.00%
Operating Income (Loss)		$ 38,506		$ 37,267	$ 126,053		$ 83,166
Total Assets	[1]	234,433			234,433				205,161
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenue	[2],[3]	93		14	110		$ 44
Percentage of total revenue	[2]						0.00%
Operating Income (Loss)	[2]	(6,432)		(12,973)	(19,308)		$ (28,717)
Total Assets	[1],[2]	449,237			449,237				393,904
CTU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue		$ 98,985		$ 96,038	$ 302,766	[4]	$ 289,650	[4]
Percentage of total revenue		58.50%		62.00%	58.70%	[4]	61.70%	[4]
Operating Income (Loss)		$ 32,993		$ 29,926	$ 100,688	[4]	$ 71,730	[4]
Total Assets	[1]	98,220			98,220				100,414
AIU [Member] | University Group [Member]
Segment Reporting Information [Line Items]
Revenue	[5]	$ 70,048	[6]	$ 58,907	$ 213,279	[6],[7]	$ 179,559	[7]
Percentage of total revenue	[5]	41.40%		38.00%	41.30%	[7]	38.30%	[7]
Operating Income (Loss)	[5]	$ 5,513		$ 7,341	$ 25,365	[7]	$ 11,436	[7]
Total Assets	[1],[5]	$ 136,213			$ 136,213				$ 104,747

[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. An expense of $7.1 million was recorded for closed campuses related to the Oregon arbitration matter for the quarter and year to date ended September 30, 2019

[3] Revenue recorded within Corporate and Other relates to certain bookstore sales and closed campuses which are now reported within this category as well as revenue not related to campus operations.

[4] An expense of $18.6 million was recorded within CTU related to the FTC settlement for the year to date ended September 30, 2019.

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

[6] AIU includes revenue related to the Trident acquisition commencing on the March 2, 2020 date of acquisition.

[7] An expense of $11.4 million was recorded within AIU related to the FTC settlement for the year to date ended September 30, 2019.