v3.8.0.1

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ 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
Quarterly Financial Information (Unaudited) |  |  |  |  |  |  |  |  |  |  |  |
Revenue | $ 86,678 | $ 70,250 | $ 64,995 | $ 64,829 | $ 57,350 | $ 51,960 | $ 49,110 | $ 47,444 |  | $ 286,752 | $ 205,864 | $ 150,194
Costs and expenses |  |  |  |  |  |  |  |  |  |  |  |
Curriculum and teaching | 4,817 | 1,792 |  |  |  |  |  |  |  | 6,609 |  |
Servicing and support | 13,445 | 12,939 | 13,458 | 10,925 | 10,859 | 10,351 | 10,260 | 9,512 |  | 50,767 | 40,982 | 32,047
Technology and content development | 12,846 | 12,735 | 11,140 | 9,205 | 8,496 | 8,670 | 8,842 | 7,275 |  | 45,926 | 33,283 | 27,211
Marketing and sales | 37,700 | 41,311 | 37,242 | 34,670 | 27,306 | 28,165 | 27,483 | 23,656 |  | 150,923 | 106,610 | 82,911
General and administrative | 17,844 | 17,227 | 13,930 | 13,664 | 13,061 | 11,569 | 10,944 | 10,447 |  | 62,665 | 46,021 | 34,123
Total costs and expenses | 86,652 | 86,004 | 75,770 | 68,464 | 59,722 | 58,755 | 57,529 | 50,890 |  | 316,890 | 226,896 | 176,292
Loss from operations | 26 | (15,754) | (10,775) | (3,635) | (2,372) | (6,795) | (8,419) | (3,446) |  | (30,138) | (21,032) | (26,098)
Interest income | 104 | 18 | 53 | 196 | 163 | 37 | 91 | 92 |  | 371 | 383 | 167
Interest expense | (50) | (36) | (1) |  |  |  | (9) | (26) |  | (87) | (35) | (552)
Other income (expense), net | 106 | 59 | (1,031) |  |  |  |  |  |  | (866) |  | (250)
Loss before income taxes | 186 | (15,713) | (11,754) | (3,439) | (2,209) | (6,758) | (8,337) | (3,380) |  | (30,720) | (20,684) | (26,733)
Income tax benefit (expense) | 323 | 974 |  |  |  |  |  |  |  | 1,297 |  |
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)
Net income (loss) per share, basic (in dollars per share) | $ 0.01 | $ (0.30) | $ (0.25) | $ (0.07) |  |  |  |  |  |  |  |
Net income (loss) per share, diluted (in dollars per share) | $ 0.01 | $ (0.30) | $ (0.25) | $ (0.07) |  |  |  |  |  |  |  |
Weighted-average shares used in computing net income (loss) per share, basic (in shares) | 52,330,067 | 48,961,914 | 47,668,397 | 47,237,341 |  |  |  |  |  |  |  |
Weighted-average shares used in computing net income (loss) per share, diluted (in shares) | 56,593,108 | 48,961,914 | 47,668,397 | 47,237,341 |  |  |  |  |  |  |  |
Net loss per share, basic and diluted (in dollars per share) |  |  |  |  | $ (0.05) | $ (0.14) | $ (0.18) | $ (0.07) |  | $ (0.60) | $ (0.44) | $ (0.63)
Weighted-average shares used in computing net loss per share, basic and diluted (in shares) |  |  |  |  | 47,075,167 | 46,903,628 | 46,494,464 | 45,953,082 |  | 49,062,611 | 46,609,751 | 42,420,356

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