Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in carrying amount
Balance, beginning of period	$ 1,318,526,000	$ 732,075,000
Reporting unit reallocation	0
Additions	0	546,053,000
Impairments	0	0	$ 0
Currency translation adjustments	(32,924,000)	40,398,000
Adjustments to prior acquisitions	262,000	0
Balance, end of period	1,285,864,000	1,318,526,000	732,075,000
U.S. Higher Education
Changes in carrying amount
Balance, beginning of period	732,075,000	732,075,000
Reporting unit reallocation	(100,000,000)
Additions	0	0
Impairments	0	0
Currency translation adjustments	0	0
Adjustments to prior acquisitions	0	0
Balance, end of period	632,075,000	732,075,000	732,075,000
Australia / New Zealand
Changes in carrying amount
Balance, beginning of period	586,451,000	0
Reporting unit reallocation	0
Additions	0	546,053,000
Impairments	0	0
Currency translation adjustments	(32,924,000)	40,398,000
Adjustments to prior acquisitions	262,000	0
Balance, end of period	553,789,000	586,451,000	0
Education Technology Services
Changes in carrying amount
Balance, beginning of period	0	0
Reporting unit reallocation	100,000,000
Additions	0	0
Impairments	0	0
Currency translation adjustments	0	0
Adjustments to prior acquisitions	0	0
Balance, end of period	$ 100,000,000	$ 0	$ 0