Revenue Recognition - Summary of Disaggregation of Revenue by Major Source (Detail) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Total revenue		$ 169,126		$ 154,959	$ 516,155		$ 469,253
University Group [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		169,033		154,945	516,045		469,209
University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		98,985		96,038	302,766	[1]	289,650	[1]
University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	70,048	[3]	58,907	213,279	[3],[4]	179,559	[4]
Corporate and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[5],[6]	93		14	110		44
Tuition [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		160,465		146,639	489,769		445,731
Tuition [Member] | University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		93,071		90,256	284,826		273,777
Tuition [Member] | University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		67,394	[3]	56,383	204,943	[3]	171,954
Technology Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		7,524		7,149	23,096		19,957
Technology Fees [Member] | University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		5,085		4,789	15,367		12,828
Technology Fees [Member] | University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		2,439	[3]	2,360	7,729	[3]	7,129
Other Miscellaneous Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[7]	482		503	1,499		1,610
Other Miscellaneous Fees [Member] | University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[7]	290		384	985		1,271
Other Miscellaneous Fees [Member] | University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[7]	192	[3]	119	514	[3]	339
Tuition and Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		168,471		154,291	514,364		467,298
Tuition and Fees [Member] | University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		98,446		95,429	301,178		287,876
Tuition and Fees [Member] | University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		70,025	[3]	58,862	213,186	[3]	179,422
Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[8]	655		668	1,791		1,955
Other [Member] | University Group [Member] | CTU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[8]	539		609	1,588		1,774
Other [Member] | University Group [Member] | AIU [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[8]	23	[3]	45	93	[3]	137
Other [Member] | Corporate and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[6],[8]	$ 93		$ 14	$ 110		$ 44

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

[2] 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.

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

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

[5] 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

[6] 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.

[7] Other miscellaneous fees include student activity fees and graduation fees.

[8] Other revenue primarily includes contract training revenue and bookstore sales.