| Contingencies and commitments - Collaborations and License Agreements (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
| Jun. 16, 2016 | Feb. 29, 2016 | Nov. 30, 2015 | Dec. 31, 2012 | Jun. 30, 2016 | |
| ThermoFisher Scientific | |||||
| Collaboration and License Agreement | |||||
| Supply contract agreement period (in years) | 5 years | ||||
| Collaborative arrangement | Universal Cells, Inc. | |||||
| Collaboration and License Agreement | |||||
| Upfront license and startup fees | $ 2.5 | ||||
| Milestone payments | $ 3.0 | ||||
| Further potential milestone payments | $ 44.0 | ||||
| Collaborative arrangement | Life Technologies Corp | |||||
| Collaboration and License Agreement | |||||
| Upfront license fees | $ 1.0 | ||||
| Minimum annual royalties as a percentage of prior year running royalties (as a percent) | 50.00% | ||||
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- Definition Represents the amount of payments that the entity is required to make under the license agreement, upon achievement of certain development and product milestones. No definition available. 
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- Definition Represents the amount of milestone payments made by the entity under the license agreement. No definition available. 
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- Definition Represents the amount of upfront and start-up fees paid. No definition available. 
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- Definition Represents the amount of upfront license fees paid. No definition available. 
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- Definition The amount to be paid as minimum annual royalties after the approval of licensed product as a percentage of prior year running royalties. No definition available. 
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- Definition Agreement period of supply contract. No definition available. 
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