Intangible assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Cost	$ 21,140
Accumulated amortization	3,071
Net book value	18,069	1,506
Marketing rights [Member]
Finite-Lived Intangible Assets [Line Items]
Marketing rights, Cost	15,830
Accumulated amortization	199
Net book value	15,631
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Trade name, Cost	1,131
Accumulated amortization	14
Net book value	1,117
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Patents, Cost	4,179	4,032
Accumulated amortization	2,858	2,526
Net book value	$ 1,321	$ 1,506

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.

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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

Gross carrying amount before accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

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Gross carrying amount before accumulated amortization as of the balance sheet date of the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a reasonably expected period of economic benefit.

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- Definition

Gross carrying amount before accumulated amortization as of the balance sheet date of intangible assets not otherwise specified in the taxonomy having a reasonably expected period of economic benefit.

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