Goodwill and Intangible Assets - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 01, 2021	Nov. 01, 2013
Business Acquisition [Line Items]
Goodwill	$ 243,486,000	$ 26,563,000	$ 26,563,000
Impairment of goodwill	0	0	7,336,000
Impairment of intangibles			0
Goodwill and intangible asset impairment	0	0
Rasmussen
Business Acquisition [Line Items]
Goodwill	217,200,000			$ 216,923,000
Indefinite-lived intangible assets acquired		51,000,000
Identified intangible assets with finite useful life		35,500,000
HCN
Business Acquisition [Line Items]
Goodwill	26,600,000	38,600,000
Fair value of goodwill			26,600,000
Impairment of goodwill		$ 0	$ 7,300,000
Indefinite-lived intangible assets acquired	3,700,000				$ 3,700,000
Identified intangible assets with finite useful life	$ 4,400,000