Fair value of financial instruments and investments - Summary of changes in the fair value of the Company's Level 3 valuation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Stock Appreciation Rights (SARs)
Changes in the fair value of warrant liability
Beginning balance	$ 3,814
Ending balance	3,186	$ 3,814
Significant unobservable inputs (level 3) \| Stock Appreciation Rights (SARs)
Changes in the fair value of warrant liability
Beginning balance	3,814	1,665
Additions	0	0
Change in fair value	3,187	4,140
Payments	(3,815)	(1,991)
Ending balance	3,186	3,814
Significant unobservable inputs (level 3) \| Agilis
Changes in the fair value of warrant liability
Ending balance	65,800
Liability, Development and Regulatory Milestone \| Agilis
Changes in the fair value of warrant liability
Beginning balance	257,040
Ending balance	290,500	257,040
Liability, Development and Regulatory Milestone \| Significant unobservable inputs (level 3) \| BioElectron \| Commitments
Changes in the fair value of warrant liability
Beginning balance	257,040	0
Additions	0	263,500
Change in fair value	33,460	(6,460)
Payments	0	0
Ending balance	290,500	257,040
Liability, Net Sales Milestones and Royalties \| Agilis
Changes in the fair value of warrant liability
Beginning balance	53,200
Ending balance	65,800	53,200
Liability, Net Sales Milestones and Royalties \| Significant unobservable inputs (level 3) \| BioElectron
Changes in the fair value of warrant liability
Beginning balance	53,200	0
Additions	0	27,000
Change in fair value	12,600	26,200
Payments	0	0
Ending balance	$ 65,800	$ 53,200

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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