Segment Reporting - Financial Information by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues
Revenues	$ 287,680	$ 273,564	$ 544,286	$ 532,419
Income from operations
Consolidated income from operations	16,817	21,865	15,468	35,306
Amortization of intangible assets	(3,450)	(3,694)	(6,982)	(7,432)
Merger and integration costs	(580)	(254)	(1,005)	(664)
Restructuring costs	(6,351)	(3,661)	(11,946)	(5,519)
Segment Reconciling Items
Income from operations
Amortization of intangible assets	(3,450)	(3,694)	(6,982)	(7,432)
Merger and integration costs	(580)	(254)	(1,005)	(664)
Restructuring costs	(6,351)	(3,661)	(11,946)	(5,519)
U.S. Higher Education
Revenues
Revenues	202,679	190,026	399,574	385,792
U.S. Higher Education \| Operating Segments
Revenues
Revenues	202,679	190,026	399,574	385,792
Income from operations
Consolidated income from operations	6,741	11,851	16,330	27,334
Australia / New Zealand
Revenues
Revenues	65,472	67,543	106,975	116,055
Australia / New Zealand \| Operating Segments
Revenues
Revenues	65,472	67,543	106,975	116,055
Income from operations
Consolidated income from operations	14,291	12,321	7,109	11,572
Education Technology Services
Revenues
Revenues	19,529	15,995	37,737	30,572
Education Technology Services \| Operating Segments
Revenues
Revenues	19,529	15,995	37,737	30,572
Income from operations
Consolidated income from operations	$ 6,166	$ 5,302	$ 11,962	$ 10,015

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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