Collaboration Agreements, License Agreement and Revenues - Roll-forward of Related Contract Liabilities (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2022 USD ($)
AstraZeneca Agreements [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	$ (171,516)
Additions	(36,184)
Currency Translation and Other	1,227
Recognized as Revenue	35,959
Balance at June 30, 2022	(170,514)
Product Revenue, Net [Member] \| Direct Sales [Member] \| Contract Liabilities [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	(3,176)
Additions	(286)
Deduction	1,903
Currency Translation and Other	157
Balance at June 30, 2022	(1,402)
Drug Product Revenue [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	(39,036)
Additions	(74,635)
Reclassified to Accrued Liability	58,644
Recognized as Revenue	90
Balance at June 30, 2022	(54,937)
Drug Product Revenue [Member] \| AstraZeneca Agreements [Member] \| U.S. [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	(11,171)
Additions	0
Reclassified to Accrued Liability	11,171
Recognized as Revenue	0
Balance at June 30, 2022	0
Drug Product Revenue [Member] \| Astellas Agreement [Member] \| Japan [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	(1,974)
Additions	(2,226)
Reclassified to Accrued Liability	4,200
Recognized as Revenue	0
Balance at June 30, 2022	0
Drug Product Revenue [Member] \| Astellas Agreement [Member] \| Europe [Member]
Contract with Customer Liability [Line Items]
Balance at December 31, 2021	(25,891)
Additions	(72,409)
Reclassified to Accrued Liability	43,273
Recognized as Revenue	90
Balance at June 30, 2022	$ (54,937)

Contract with customer liability additions.

No definition available.

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- Definition

Contract with customer liability deduction.

+ References

No definition available.

+ Details

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- Definition

Contract with customer, liability, increase (decrease) from current translation and other.

+ References

No definition available.

+ Details

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- Definition

Contract with customer liability.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Contract with customer liability reclassified to accrued liability.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=126919976&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130549-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126919976&loc=SL49130532-203044

+ Details

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Balance Type:	credit
Period Type:	instant

- 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
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130549-203045

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