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Fair Value Measurements (Details) $ in Thousands	Jul. 31, 2019 USD ($)	Dec. 11, 2018 USD ($)	Dec. 11, 2018 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, gross				$ 293,250	$ 294,000	$ 336,250
Accounts Receivable \| Credit extension program
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure				$ 33,000	$ 34,300	$ 38,100
DeVry University [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Receivable with Imputed Interest, Face Amount		$ 10,000	$ 10,000
Receivable with Imputed Interest, Effective Yield (Interest Rate)		4.00%	4.00%
Receivable with Imputed Interest, Due Date		Jan. 01, 2022	Jan. 01, 2022
DeVry University [Member] \| Discount rate \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Measurement Input				0.04	0.04	0.04
DeVry University [Member] \| Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure				$ 10,000	$ 10,000	$ 10,000
Chicago, Illinois Campus [Member] \| Discontinued Operations, Disposed of by Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure				$ 41,700	$ 41,400	$ 40,400
Receivable with Imputed Interest, Face Amount	$ 46,800
Receivable with Imputed Interest, Effective Yield (Interest Rate)	4.00%
Receivable with Imputed Interest, Due Date	Jul. 31, 2024
Chicago, Illinois Campus [Member] \| Discount rate \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Measurement Input				0.07	0.07	0.07
Chicago, Illinois Campus [Member] \| Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure				$ 41,700	$ 41,400	$ 40,400
Interest Rate Swap \| Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset				$ 10,200	$ 10,400