Stock-Based Compensation (Total Stock-Based Compensation Expense Included in Consolidated Statement of Income) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	$ 3,648	$ 3,324	$ 7,652	$ 8,547
Income Tax Benefit	(641)	(713)	(1,167)	(3,246)
Net Stock-Based Compensation Expense	3,007	2,611	6,485	5,301
Cost of Educational Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	345	312	738	767
Student Services And Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	$ 3,303	$ 3,012	$ 6,914	$ 7,780

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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