v3.10.0.1

Stock-Based Compensation - Expense (Details) |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jun. 05, 2017 USD ($) | Sep. 30, 2018 USD ($) plan | Sep. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) plan | Sep. 30, 2017 USD ($)
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Number of share-based employee compensation plans | plan |  | 2 |  | 2 |
Percentage of purchase price to fair market value | 90.00% |  |  |  |
Maximum payroll deduction amount per calendar year | $ 25,000 |  |  |  |
Stock-based compensation expense |  | $ 7,933,000 | $ 6,147,000 | $ 24,064,000 | $ 15,537,000
Curriculum and teaching |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Stock-based compensation expense |  | 3,000 | 2,000 | 10,000 | 2,000
Servicing and support |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Stock-based compensation expense |  | 1,346,000 | 1,100,000 | 3,538,000 | 2,956,000
Technology and content development |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Stock-based compensation expense |  | 1,089,000 | 904,000 | 2,875,000 | 2,447,000
Marketing and sales |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Stock-based compensation expense |  | 839,000 | 463,000 | 2,046,000 | 1,235,000
General and administrative |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Stock-based compensation expense |  | $ 4,656,000 | $ 3,678,000 | $ 15,595,000 | $ 8,897,000
Minimum |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Percentage of payroll deduction | 1.00% |  |  |  |
Maximum |  |  |  |  |
Stock-based compensation expense included in the unaudited condensed consolidated statements of operations |  |  |  |  |
Percentage of payroll deduction | 15.00% |  |  |  |

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