Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($)	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Changes in carrying amount
Balance, beginning of period	$ 1,251,888,000
Additions	0
Impairments	0	$ 0
Currency translation adjustments	(22,006,000)
Adjustments to prior acquisitions	0
Balance, end of period	1,229,882,000
U.S. Higher Education
Changes in carrying amount
Balance, beginning of period	632,075,000
Additions	0
Impairments	0
Currency translation adjustments	0
Adjustments to prior acquisitions	0
Balance, end of period	632,075,000
Australia / New Zealand
Changes in carrying amount
Balance, beginning of period	519,813,000
Additions	0
Impairments	0
Currency translation adjustments	(22,006,000)
Adjustments to prior acquisitions	0
Balance, end of period	497,807,000
Education Technology Services
Changes in carrying amount
Balance, beginning of period	100,000,000
Additions	0
Impairments	0
Currency translation adjustments	0
Adjustments to prior acquisitions	0
Balance, end of period	$ 100,000,000

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