Goodwill and intangible assets (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets, Future Amortization Expense [Line Items]
2015	$ 644
2016	644
2017	325
2018	285
2019	283
Thereafter	236
Total	2,417us-gaap_FiniteLivedIntangibleAssetsNet	2,423us-gaap_FiniteLivedIntangibleAssetsNet
Trademarks [Member]
Finite-Lived Intangible Assets, Future Amortization Expense [Line Items]
2015	3
2016	2
2017	0
2018	0
2019	0
Thereafter	0
Total	5
Intellectual Property [Member]
Finite-Lived Intangible Assets, Future Amortization Expense [Line Items]
2015	283
2016	283
2017	283
2018	283
2019	283
Thereafter	236
Total	1,651
Software And Website Development [Member]
Finite-Lived Intangible Assets, Future Amortization Expense [Line Items]
2015	316
2016	317
2017	0
2018	0
2019	0
Thereafter	0
Total	633
Customer Lists [Member]
Finite-Lived Intangible Assets, Future Amortization Expense [Line Items]
2015	42
2016	42
2017	42
2018	2
2019	0
Thereafter	0
Total	$ 128

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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)(3)

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

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

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

+ References

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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