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Represents the cash obligation by the entity to pay upon achievement of certain milestones based on terms of collaboration agreement.

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No definition available.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

Represents the upfront license and option fee payment relating to exclusive collaboration license and development agreement.

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No definition available.

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- Definition

Balance held at close of period in number of shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
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- Definition

Cash outflow for purchase of trading, available-for-sale securities and held-to-maturity securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Collaboration and Commercial Technology Licensing Agreements (Biocartis) (Details) $ / shares in Units, $ in Thousands, € in Millions	1 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2017 EUR (€)	Dec. 31, 2017 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 EUR (€)	Dec. 31, 2017 USD ($) $ / shares shares	Sep. 30, 2017 EUR (€)
Collaboration agreements
Amount invested			$ 64,388	$ 50,338
Exclusive license and development agreement with Biocartis NV
Collaboration agreements
Number of shares purchased \| shares		270,000				270,000
Market price \| $ / shares		$ 12.50				$ 12.50
Amount invested	€ 3.4	$ 4,000
Estimated fair value		$ 3,500	$ 3,700			$ 3,500
Cash obligation upon achievement of certain milestones \| €							€ 6.5
Exclusive license and development agreement with Biocartis NV \| Research and development
Collaboration agreements
Upfront license and option fee payment					€ 2.8	$ 3,200