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, 2020	Dec. 31, 2019
SARs
Changes in the fair value of warrant liability and SARs liability
Ending Balance	$ 0
Level 3
Changes in the fair value of warrant liability and SARs liability
Ending Balance	101,200
Level 3 \| SARs
Changes in the fair value of warrant liability and SARs liability
Beginning Balance	3,186	$ 3,814
Additions	0	0
Change in fair value	0	3,187
Payments	(3,186)	(3,815)
Rights Exchange settlement	0
Ending Balance	0	3,186
Development and Regulatory Milestone \| Level 3 \| Agilis \| Contingent Consideration Payable
Changes in the fair value of warrant liability and SARs liability
Beginning Balance	290,500	257,040
Additions	0	0
Change in fair value	(12,120)	33,460
Payments	0	0
Rights Exchange settlement	(139,180)
Ending Balance	139,200	290,500
Net Sales Milestones and Royalties \| Level 3 \| Agilis \| Contingent Consideration Payable
Changes in the fair value of warrant liability and SARs liability
Beginning Balance	65,800	53,200
Additions	0	0
Change in fair value	35,400	12,600
Payments	0	0
Rights Exchange settlement	0
Ending Balance	$ 101,200	$ 65,800

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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Amount of 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
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-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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