v3.20.1

Stock-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	$ 20,870	$ 9,584
Curriculum and teaching
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	133	3
Servicing and support
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	3,928	1,669
Technology and content development
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	3,169	1,856
Marketing and sales
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	3,233	1,256
General and administrative
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations
Stock-based compensation expense	$ 10,407	$ 4,800

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
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