v3.19.3.a.u2

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 51,504	$ 31,410	$ 21,930
Curriculum and teaching
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	45	14	3
Servicing and support
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	8,915	4,764	4,036
Technology and content development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	8,241	4,094	3,306
Marketing and sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7,021	2,743	1,742
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 27,282	$ 19,795	$ 12,843

X

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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+ References

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