Segment and Geographic Information - Schedule of Non-cash items (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	$ 57,313	$ 63,124	$ 103,416
Amortization of intangible assets	11,457	14,350	51,495
Stock-based compensation	19,772	21,792	18,149
Segments \| U.S. Higher Education
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	33,655	35,863	38,178
Stock-based compensation	17,653	19,572	16,926
Segments \| Australia / New Zealand
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	8,954	8,842	10,640
Stock-based compensation	(117)	1,073	1,359
Segments \| Education Technology Services
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	2,526	1,589	1,067
Stock-based compensation	1,729	1,147	567
Segment Reconciling Items
Non cash items included in segment income (loss) from operations by reportable segment
Amortization of intangible assets	11,457	14,350	51,495
Merger and integration costs	336	0	0
Restructuring costs	385	2,480	2,036
Restructuring costs	$ 507	$ 0	$ (703)

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount of expense (income) related to the increase (decrease) in reserve for business combination costs. Includes, but is not limited to, legal, accounting, and other costs incurred to consummate the merger.

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Amount of noncash expense for share-based payment arrangement.

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