Segment Reporting - Financial Information by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Revenues
Revenues	$ 290,336	$ 265,302
Income (loss) from operations
Income (loss) from operations	12,000	43,959
Amortization of intangible assets	(19,407)	(15,417)
Merger and integration costs	(1,012)	(3,764)
Restructuring costs	(18,267)	0
U.S. Higher Education
Revenues
Revenues	226,547	255,513
Income (loss) from operations
Income (loss) from operations	47,754	56,743
Australia / New Zealand
Revenues
Revenues	51,265	0
Income (loss) from operations
Income (loss) from operations	(2,949)	0
Alternative Learning
Revenues
Revenues	12,524	9,789
Income (loss) from operations
Income (loss) from operations	$ 5,881	$ 6,397

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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