v3.10.0.1

Summary of significant accounting policies - Adoption of ASC 606 (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Jan. 01, 2018 | Dec. 31, 2017
Adoption of ASC 606 |  |  |  |  |  |
Accumulated deficit | $ (130,346) |  | $ (130,346) |  |  | $ (131,967)
Accounts receivable, net | 30,659 |  | 30,659 |  | $ 25,079 | 26,148
Prepaid expenses and other current assets | 9,013 |  | 9,013 |  | 6,539 | 6,369
Other assets | 7,999 |  | 7,999 |  | 7,903 | 10,082
Deferred revenue, current | 78,825 |  | 78,825 |  | 75,884 | 61,708
Deferred revenue, net of current portion | 127,911 |  | 127,911 |  | 128,588 | 149,168
Non-controlling interests | 2,181 |  | 2,181 |  |  | 1,212
Revenue | 65,253 | $ 53,655 | 183,013 | $ 147,021 |  |
Income tax expense | 54 | 167 | 198 | 507 |  |
Non-controlling interests | 596 | $ 210 | 1,447 | $ 477 |  |
Adjustment for adoption |  |  |  |  |  |
Adoption of ASC 606 |  |  |  |  |  |
Accounts receivable, net |  |  |  |  | (1,069) |
Prepaid expenses and other current assets |  |  |  |  | 170 |
Other assets |  |  |  |  | (2,179) |
Deferred revenue, current |  |  |  |  | 14,176 |
Deferred revenue, net of current portion |  |  |  |  | (20,580) |
ASC 606 | As per ASC 605 |  |  |  |  |  |
Adoption of ASC 606 |  |  |  |  |  |
Accounts receivable, net | 31,367 |  | 31,367 |  |  | 26,148
Prepaid expenses and other current assets | 8,522 |  | 8,522 |  |  | 6,369
Other assets | 10,213 |  | 10,213 |  |  | 10,082
Deferred revenue, current | 79,738 |  | 79,738 |  |  | 61,708
Deferred revenue, net of current portion | 140,040 |  | 140,040 |  |  | $ 149,168
Non-controlling interests | 228 |  | 228 |  |  |
Revenue | 63,884 |  | 176,168 |  |  |
Income tax expense | 258 |  | 638 |  |  |
Non-controlling interests | 270 |  | (437) |  |  |
ASC 606 | Adjustment for adoption |  |  |  |  |  |
Adoption of ASC 606 |  |  |  |  |  |
Accumulated deficit |  |  |  |  | 3,257 |
Accounts receivable, net | (708) |  | (708) |  |  |
Prepaid expenses and other current assets | 491 |  | 491 |  |  |
Other assets | (2,214) |  | (2,214) |  |  |
Deferred revenue, current | (913) |  | (913) |  |  |
Deferred revenue, net of current portion | (12,129) |  | (12,129) |  |  |
Non-controlling interests | 1,953 |  | 1,953 |  | $ 69 |
Revenue | 1,369 |  | 6,845 |  |  |
Income tax expense | (204) |  | (440) |  |  |
Non-controlling interests | $ 326 |  | $ 1,884 |  |  |

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