v2.4.1.9

Summary of significant accounting policies (Details 3) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 item | Dec. 31, 2013
Goodwill |  |
Number of reporting units | 1 us-gaap_NumberOfReportingUnits |
Number of operating segments | 1 us-gaap_NumberOfOperatingSegments |
Number of reportable segments | 1 us-gaap_NumberOfReportableSegments |
Goodwill impairment charges | $ 0 us-gaap_GoodwillImpairmentLoss | $ 0 us-gaap_GoodwillImpairmentLoss
Computer equipment | Minimum |  |
Property and equipment |  |
Estimated useful lives | 2 years |
Computer equipment | Maximum |  |
Property and equipment |  |
Estimated useful lives | 5 years |
Software | Minimum |  |
Property and equipment |  |
Estimated useful lives | 2 years |
Software | Maximum |  |
Property and equipment |  |
Estimated useful lives | 5 years |
Office equipment | Minimum |  |
Property and equipment |  |
Estimated useful lives | 3 years |
Office equipment | Maximum |  |
Property and equipment |  |
Estimated useful lives | 5 years |
Leasehold improvements | Minimum |  |
Property and equipment |  |
Estimated useful lives | 2 years |
Leasehold improvements | Maximum |  |
Property and equipment |  |
Estimated useful lives | 15 years |

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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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- Definition Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Reporting Unit -URI http://asc.fasb.org/extlink&oid=6523643 + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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