v3.8.0.1

Goodwill and Amortizable Intangible Assets (Tables) | 12 Months Ended
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Dec. 31, 2017
Goodwill and Amortizable Intangible Assets |
Schedule of amortizable intangible assets |
|  |  |  | December 31, 2017 |  | December 31, 2016 |
|  | Estimated Average Useful Life (in years) |  | Gross Carrying Amount |  | Accumulated Amortization |  | Net Carrying Amount |  | Gross Carrying Amount |  | Accumulated Amortization |  | Net Carrying Amount |
|  |  |  | (in thousands) |
Capitalized technology |  | 3 |  | $ | 27,108 |  | $ | (9,486 | ) | $ | 17,622 |  | $ | 17,100 |  | $ | (7,822 | ) | $ | 9,278 |
Capitalized content development |  | 4 |  |  | 55,872 |  |  | (21,417 | ) |  | 34,455 |  |  | 37,956 |  |  | (15,367 | ) |  | 22,589 |
University client relationships |  | 9 |  |  | 29,443 |  |  | (1,636 | ) |  | 27,807 |  |  | — |  |  | — |  |  | — |
Trade names and domain names |  | 10 |  |  | 12,119 |  |  | (1,242 | ) |  | 10,877 |  |  | 2,761 |  |  | (497 | ) |  | 2,264 |
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Total amortizable intangible assets, net |  |  |  | $ | 124,542 |  | $ | (33,781 | ) | $ | 90,761 |  | $ | 57,817 |  | $ | (23,686 | ) | $ | 34,131 |
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Schedule of estimated future amortization expense for amortizable intangible assets | As of December 31, 2017, the estimated future amortization expense for amortizable intangible assets placed in service is as follows (in thousands):
2018 |  | $ | 17,571 |
2019 |  |  | 15,595 |
2020 |  |  | 12,102 |
2021 |  |  | 8,216 |
2022 |  |  | 5,404 |
Thereafter |  |  | 16,296 |
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Total |  | $ | 75,184 |
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