v3.8.0.1

Summary of significant accounting policies - Adoption of ASC 606 (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Jan. 01, 2018 | Dec. 31, 2017
Adoption of ASC 606 |  |  |  |
Accumulated deficit | $ (131,939) |  |  | $ (131,967)
Accounts receivable, net | 28,861 |  | $ 25,079 | 26,148
Prepaid expenses and other current assets | 6,482 |  | 6,539 | 6,369
Other assets | 7,577 |  | 7,903 | 10,082
Deferred revenue, current | 76,340 |  | 75,884 | 61,708
Deferred revenue, net of current portion | 125,174 |  | 128,588 | 149,168
Non-controlling interests | 1,734 |  |  | 1,212
Revenue | 58,159 | $ 44,333 |  |
Income tax expense | 128 | 199 |  |
Non-controlling interests | 456 | $ 107 |  |
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 | 29,286 |  |  | 26,148
Prepaid expenses and other current assets | 6,567 |  |  | 6,369
Other assets | 9,910 |  |  | 10,082
Deferred revenue, current | 67,423 |  |  | 61,708
Deferred revenue, net of current portion | 144,652 |  |  | $ 149,168
Non-controlling interests | 370 |  |  |
Revenue | 53,890 |  |  |
Income tax expense | 251 |  |  |
Non-controlling interests | (839) |  |  |
ASC 606 | Adjustment for adoption |  |  |  |
Adoption of ASC 606 |  |  |  |
Accumulated deficit |  |  | 3,257 |
Accounts receivable, net | (425) |  |  |
Prepaid expenses and other current assets | (85) |  |  |
Other assets | (2,333) |  |  |
Deferred revenue, current | 8,917 |  |  |
Deferred revenue, net of current portion | (19,478) |  |  |
Non-controlling interests | 1,364 |  | $ 69 |
Revenue | 4,269 |  |  |
Income tax expense | (123) |  |  |
Non-controlling interests | $ 1,295 |  |  |

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- Definition Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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