Collaboration Agreements, License Agreement and Revenues - Transaction Price Related to Consideration Received and Accounts Receivable Allocated to Performance Obligations Deferred Revenue (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Deferred revenue, net of current ($26,285 and $25,891 to a related party)	$ 184,893	$ 186,801
AstraZeneca Agreements [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Deferred Revenue	171,238	$ 171,516
AstraZeneca Agreements [Member] \| U.S./RoW [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Deferred revenue, net of current ($26,285 and $25,891 to a related party)	160,000
Deferred Revenue	171,200
Net unbilled co-development revenue	$ 11,200

Collaboration Agreements, License Agreement and Revenues - Transaction Price Related to Consideration Received and Accounts Receivable Allocated to Performance Obligations Deferred Revenue (Parenthetical) (Detail) - USD ($)
$ in Thousands

Mar. 31, 2022

Dec. 31, 2021

Revenue Recognition, Multiple-deliverable Arrangements [Line Items]

Deferred revenue, net of current ($26,285 and $25,891 to a related party)

$ 184,893

$ 186,801

AstraZeneca Agreements [Member]

Revenue Recognition, Multiple-deliverable Arrangements [Line Items]

Deferred Revenue

171,238

$ 171,516

AstraZeneca Agreements [Member] | U.S./RoW [Member]

Revenue Recognition, Multiple-deliverable Arrangements [Line Items]

Deferred revenue, net of current ($26,285 and $25,891 to a related party)

160,000

Deferred Revenue

171,200

Net unbilled co-development revenue

$ 11,200