v3.20.2

Goodwill and Amortizable Intangible Assets - Amortizable Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning balance	$ 418,350
Foreign currency translation adjustments	(10,490)
Ending balance	407,860
Gross Carrying Amount	489,729	$ 447,276
Accumulated Amortization	(173,324)	(114,201)
Total	316,405	333,075
Graduate Program Segment
Goodwill [Roll Forward]
Beginning balance	0
Foreign currency translation adjustments	0
Ending balance	0
Alternative Credential Segment
Goodwill [Roll Forward]
Beginning balance	418,350
Foreign currency translation adjustments	(10,490)
Ending balance	407,860
Capitalized technology
Goodwill [Roll Forward]
Gross Carrying Amount	159,164	142,712
Accumulated Amortization	(66,861)	(41,106)
Total	$ 92,303	101,606
Capitalized technology | Minimum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	3 years
Capitalized technology | Maximum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	5 years
Capitalized content development
Goodwill [Roll Forward]
Gross Carrying Amount	$ 198,568	167,758
Accumulated Amortization	(78,729)	(54,736)
Total	$ 119,839	113,022
Capitalized content development | Minimum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	4 years
Capitalized content development | Maximum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	5 years
University client relationships
Goodwill [Roll Forward]
Gross Carrying Amount	$ 106,384	110,344
Accumulated Amortization	(19,483)	(12,419)
Total	$ 86,901	97,925
University client relationships | Minimum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	9 years
University client relationships | Maximum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	10 years
Trade names and domain names
Goodwill [Roll Forward]
Gross Carrying Amount	$ 25,613	26,462
Accumulated Amortization	(8,251)	(5,940)
Total	$ 17,362	$ 20,522
Trade names and domain names | Minimum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	5 years
Trade names and domain names | Maximum
Goodwill [Roll Forward]
Estimated Average Useful Life (in years)	10 years

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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