Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		18 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023
Summary of Significant Accounting Policies
Revenues	$ 504,868	$ 458,435	$ 985,049	$ 883,585
Percentage of impact on total revenue					2.00%
School operating losses included in the entity's revenue	3,100	6,400	$ 8,300	16,600
Minimum
Summary of Significant Accounting Policies
Duration of contracts providing access to curriculum via the entity's Web site			1 year
Maximum
Summary of Significant Accounting Policies
Duration of contracts providing access to curriculum via the entity's Web site			2 years
Primary Obligor
Summary of Significant Accounting Policies
Revenues	$ 142,500	$ 123,000	$ 278,600	$ 248,300