Segment and Geographic Information - Non-cash items (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	$ 63,124	$ 103,416	$ 109,154
Amortization of intangible assets	14,350	51,495	64,225
Stock-based compensation	21,792	18,149	14,610
Segments \| U.S. Higher Education
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	35,863	38,178	41,822
Stock-based compensation	19,572	16,926	14,452
Segments \| Australia / New Zealand
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	8,842	10,640	1,930
Stock-based compensation	1,073	1,359	46
Segments \| Education Technology Services
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	1,589	1,067	828
Stock-based compensation	1,147	567	112
Segment Reconciling Items
Non cash items included in segment income (loss) from operations by reportable segment
Amortization of intangible assets	14,350	51,495	64,225
Restructuring costs	2,480	2,036	349
Restructuring costs	$ 0	$ (703)	$ 0

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Stock Based Compensation Restructing Costs

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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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