v3.8.0.1

Segment and Geographic Information - Segment Performance (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Revenue by segment |  |  |  |  |  |  |  |  |  |  |  |
Total segment revenue | $ 86,678 | $ 70,250 | $ 64,995 | $ 64,829 | $ 57,350 | $ 51,960 | $ 49,110 | $ 47,444 |  | $ 286,752 | $ 205,864 | $ 150,194
Profitability by Segment |  |  |  |  |  |  |  |  |  |  |  |
Total Segment Profitability |  |  |  |  |  |  |  |  |  | $ 11,416 | $ 4,541 | $ (6,629)
Segment profitability margin |  |  |  |  |  |  |  |  |  |  |  |
Total segment profitability margin (in percent) |  |  |  |  |  |  |  |  |  | 4.00% | 2.00% | (4.00%)
Net loss |  |  |  |  |  |  |  |  |  |  |  |
Net loss | 509 | (14,739) | (11,754) | (3,439) | (2,209) | (6,758) | (8,337) | (3,380) | $ (29,423) | $ (29,423) | $ (20,684) | $ (26,733)
Adjustments |  |  |  |  |  |  |  |  |  |  |  |
Interest income | (104) | (18) | (53) | $ (196) | (163) | $ (37) | (91) | (92) |  | (371) | (383) | (167)
Interest expense | 50 | 36 | $ 1 |  |  |  | $ 9 | $ 26 |  | 87 | 35 | 552
Foreign currency loss |  |  |  |  |  |  |  |  |  | 866 |  |
Depreciation and amortization expense |  |  |  |  |  |  |  |  |  | 19,624 | 9,750 | 7,220
Income tax benefit | (323) | $ (974) |  |  |  |  |  |  |  | (1,297) |  |
Stock-based compensation expense |  |  |  |  |  |  |  |  |  | 21,930 | 15,823 | 12,499
Total adjustments |  |  |  |  |  |  |  |  |  | 40,839 | 25,225 | 20,104
Total assets |  |  |  |  |  |  |  |  |  |  |  |
Total assets | 482,062 |  |  |  | 244,320 |  |  |  | 482,062 | 482,062 | 244,320 |
Graduate Program Segment |  |  |  |  |  |  |  |  |  |  |  |
Revenue by segment |  |  |  |  |  |  |  |  |  |  |  |
Total segment revenue |  |  |  |  |  |  |  |  |  | 270,432 | 205,864 | 150,194
Profitability by Segment |  |  |  |  |  |  |  |  |  |  |  |
Total Segment Profitability |  |  |  |  |  |  |  |  |  | $ 13,022 | $ 4,541 | $ (6,629)
Segment profitability margin |  |  |  |  |  |  |  |  |  |  |  |
Total segment profitability margin (in percent) |  |  |  |  |  |  |  |  |  | 5.00% | 2.00% | (4.00%)
Total assets |  |  |  |  |  |  |  |  |  |  |  |
Total assets | 359,597 |  |  |  | $ 244,320 |  |  |  | 359,597 | $ 359,597 | $ 244,320 |
Short Course Segment |  |  |  |  |  |  |  |  |  |  |  |
Revenue by segment |  |  |  |  |  |  |  |  |  |  |  |
Total segment revenue |  |  |  |  |  |  |  |  |  | 16,320 |  |
Profitability by Segment |  |  |  |  |  |  |  |  |  |  |  |
Total Segment Profitability |  |  |  |  |  |  |  |  |  | $ (1,606) |  |
Segment profitability margin |  |  |  |  |  |  |  |  |  |  |  |
Total segment profitability margin (in percent) |  |  |  |  |  |  |  |  |  | (1.00%) |  |
Total assets |  |  |  |  |  |  |  |  |  |  |  |
Total assets | $ 122,465 |  |  |  |  |  |  |  | $ 122,465 | $ 122,465 |  |

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