Cash, restricted cash, cash equivalents, and available for sale investments.

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- Definition

Organization and summary of significant accounting policies.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 9
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4531-111522

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(5))
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

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- Definition

The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

+ References

No definition available.

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Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Organization And Summary Of Significant Accounting Policies [Line Items]
Cash and investments in marketable securities		$ 628,244,000		$ 628,244,000		$ 798,783,000
Accounts receivable		10,006,000		10,006,000		22,492,000
Accounts receivable, credit loss expense (reversal)		0	$ 0	0	$ 0
Employee Severance
Organization And Summary Of Significant Accounting Policies [Line Items]
Workforce termination, percentage	70.00%
Bristol Myers Squibb Collaboration Agreement
Organization And Summary Of Significant Accounting Policies [Line Items]
Accounts receivable		$ 7,400,000		$ 7,400,000		$ 21,400,000