Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Changes in carrying amount
Balance, beginning of period	$ 1,318,526,000
Reporting unit reallocation	0
Additions	0
Impairments	0	$ 0
Currency translation adjustments	(7,301,000)
Adjustments to prior acquisitions	262,000
Balance, end of period	1,311,487,000
U.S. Higher Education
Changes in carrying amount
Balance, beginning of period	732,075,000
Reporting unit reallocation	(100,000,000)
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	586,451,000
Reporting unit reallocation	0
Additions	0
Impairments	0
Currency translation adjustments	(7,301,000)
Adjustments to prior acquisitions	262,000
Balance, end of period	579,412,000
Alternative Learning
Changes in carrying amount
Balance, beginning of period	0
Reporting unit reallocation	100,000,000
Additions	0
Impairments	0
Currency translation adjustments	0
Adjustments to prior acquisitions	0
Balance, end of period	$ 100,000,000

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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