Goodwill and intangible assets (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Less: Accumulated amortization	$ (979)	$ (486)
Intangible assets, net	2,417us-gaap_FiniteLivedIntangibleAssetsNet	2,423us-gaap_FiniteLivedIntangibleAssetsNet
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Finite-Lived Intangible Assets, Gross	5	7
Intangible assets, net	5
Intellectual Property [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 years
Finite-Lived Intangible Assets, Gross	2,230	2,468
Intangible assets, net	1,651
Software And Website Development [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Finite-Lived Intangible Assets, Gross	951	275
Intangible assets, net	633
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Finite-Lived Intangible Assets, Gross	210	159
Intangible assets, net	$ 128

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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