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Goodwill and Intangible Assets - Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Adjustments to prior acquisitions	$ 0	$ 465,000
Impairment of goodwill	0	0
JWMI
Goodwill [Line Items]
Impairment of goodwill	0
Capella University
Goodwill [Line Items]
Adjustments to prior acquisitions	0	465,000
Impairment of goodwill	0	0
Strayer University
Goodwill [Line Items]
Adjustments to prior acquisitions	0	0
Impairment of goodwill	0	0
Impairment of intangible assets	$ 0	0
Capella Merger
Goodwill [Line Items]
Adjustments to prior acquisitions		$ 500,000
New York Code And Design Academy, Inc.
Goodwill [Line Items]
Impairment of goodwill			$ 13,900,000