Expense or accruals recognized related to royalties.

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- Definition

Expense related to milestone payments.

+ References

No definition available.

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- Definition

First commercial sale of a licensed product period.

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No definition available.

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- Definition

Long term purchase commitment additional obligation to be paid.

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No definition available.

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Long term purchase commitment period description.

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- Definition

Milestone payments and royalties receivable.

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No definition available.

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- Definition

Research and development arrangement contract to perform for others expiry period.

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No definition available.

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- Definition

Upfront license fees paid

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No definition available.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

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- Definition

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The fair value of notes issued in noncash investing and financing activities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The amount of cash paid for royalties during the current period.

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- Definition

The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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License and collaboration agreements - Additional Information (Detail) - USD ($)		1 Months Ended		3 Months Ended		11 Months Ended	12 Months Ended
	Jun. 25, 2020	Jun. 30, 2020	Apr. 30, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2020	Dec. 19, 2018	Aug. 16, 2018	Jun. 30, 2018
Expense related to milestone payments				$ 0
KU Leuven [Member]
Collaboration expire period	2 years 6 months
Emory license agreement [Member] \| Emory university [Member]
Non-refundable payment		$ 150,000
Long term purchase commitment additional obligation to be paid		35,000
Research plan funding amount		$ 270,000
Research plan expiry period		1 year
Long term purchase commitment period description				The research plan terminates one year from the effective date, with the Company having an option to extend for a second year.
Expense related to milestone payments				$ 80,000
Payments for royalties				0	$ 0
Expense or accruals recognized related to royalties				0	0
Emory license agreement [Member] \| Emory university [Member] \| Maximum [Member]
Aggregate payments											$ 125,000,000
Emory license agreement [Member] \| Series A \| Emory university [Member]
Debt instrument, conversion price										$ 9.32
Luxna license agreement [Member] \| Luxna biotech Co Ltd [Member]
Expense related to milestone payments				0	0
Payments for royalties				$ 0	0
Luxna license agreement [Member] \| Luxna biotech Co Ltd [Member] \| Maximum [Member]
Aggregate payments									$ 55,500,000
Katholieke Universiteit Leuven License Agreement [Member] \| Katholieke Universiteit Leuven [Member]
Non-refundable payment	$ 30,000,000
Long term purchase commitment period description				Unless terminated earlier by either party, the agreement shall continue until the expiration of the last to expire royalty term, which is the later of the expiration or termination of the last valid patent claim covering the manufacture, use, sale or importation of the licensed product in a particular country or 10 years after the first commercial sale of a licensed product.
First commercial sale of a licensed product period	10 years
Katholieke Universiteit Leuven License Agreement [Member] \| Katholieke Universiteit Leuven [Member] \| Maximum [Member]
Non-refundable payment	$ 32,000,000
Merck License and Research Collaboration [Member] \| Merck [Member]
Revenue recognized from collaborative arrangements				$ 910,000	$ 0
Merck License and Research Collaboration [Member] \| Merck [Member] \| Maximum [Member]
Milestone payments and royalties receivable								$ 458,000,000
Research and Development [Member] \| Emory license agreement [Member] \| Emory university [Member]
Upfront license fees paid				290,000
Convertible notes issued for purchasing license				$ 600,000
Research and Development [Member] \| Luxna license agreement [Member] \| Luxna biotech Co Ltd [Member]
Upfront license fees paid						$ 600,000	$ 600,000
Non-refundable payment			$ 200,000