Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in carrying amount
Balance, beginning of period	$ 732,540	$ 20,744
Additions		723,929
Impairments	0	(13,944)	$ 0
Measurement period adjustment, goodwill	(465)	1,811
Balance, end of period	732,075	732,540	20,744
Strayer University
Changes in carrying amount
Balance, beginning of period	337,381	6,800
Additions		330,581
Balance, end of period	337,381	337,381	6,800
Capella University
Changes in carrying amount
Balance, beginning of period	395,159
Additions		393,348
Impairments	0
Measurement period adjustment, goodwill	(465)	1,811
Balance, end of period	394,694	395,159
JWMI
Changes in carrying amount
Impairments	0
Non-Degree Programs
Changes in carrying amount
Balance, beginning of period	$ 0	13,944
Impairments		(13,944)
Measurement period adjustment, goodwill		0
Balance, end of period		$ 0	$ 13,944

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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