Segment Reporting - Financial Information by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenues
Revenues	$ 273,564	$ 299,173	$ 532,419	$ 589,509
Income from operations
Income from operations	21,865	26,700	35,306	38,700
Amortization of intangible assets	(3,694)	(19,392)	(7,432)	(38,799)
Merger and integration costs	(254)	(1,937)	(664)	(2,949)
Restructuring costs	(3,661)	(4,811)	(5,519)	(23,078)
U.S. Higher Education
Revenues
Revenues	190,026	212,207	385,792	438,754
Income from operations
Income from operations	11,851	32,059	27,334	79,813
Australia / New Zealand
Revenues
Revenues	67,543	74,060	116,055	125,325
Income from operations
Income from operations	12,321	15,601	11,572	12,652
Education Technology Services
Revenues
Revenues	15,995	12,906	30,572	25,430
Income from operations
Income from operations	$ 5,302	$ 5,180	$ 10,015	$ 11,061

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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