Collaborations and License Agreements - Additional Information (Detail)		1 Months Ended																						3 Months Ended				12 Months Ended
	Aug. 02, 2020 USD ($)	Aug. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	May 31, 2019 USD ($)	Feb. 28, 2019 USD ($)	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Nov. 30, 2018 USD ($)	Oct. 31, 2018 USD ($)	Aug. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Feb. 28, 2018 USD ($)	Oct. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Apr. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2012 USD ($)	Mar. 31, 2010 USD ($)	Dec. 31, 2006 USD ($)	Mar. 31, 2021 USD ($) Installment Indication	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2020 USD ($)	Aug. 31, 2019 USD ($)	Apr. 30, 2014
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement month and date																								2018-12
Trade receivables, net																								$ 1,144,000					$ 1,197,000
Revenue recognized as collaboration and licensing revenue related to the cumulative catch-up																		$ 2,500,000
Amounts due from pursuant to the cost-sharing provisions																								1,144,000					$ 1,197,000
Revenues																								1,920,000		$ 784,000
Partnership Royalties
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues																								361,000		291,000
Astra Zeneca Inc. | Astra Zeneca Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Trade receivables, net																								400,000
Amounts due from pursuant to the cost-sharing provisions																								$ 400,000
CANbridge
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement date																								Mar. 31, 2016
Allocation of upfront payment											$ 700,000
CANbridge | Licensing Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received																			$ 1,000,000.0
Upfront payment, withholding taxes																			$ 100,000
Number of installments paid | Installment																								2
Revenue recognized from reimbursement of manufacturing development activities																$ 500,000	$ 500,000							$ 1,000,000.0
CANbridge | Licensing Agreements | Development and Regulatory Milestone Events
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and licensing revenue											2,000,000.0
CANbridge | Licensing Agreements | Development and Regulatory Milestone Events
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and licensing revenue											2,000,000.0
EUSA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement received																4,000,000.0												$ 2,500,000
Percentage of EUSA cost-sharing for TIVO-3 trial																								50.00%
Collaborations and license agreements, expected milestone receivable						$ 2,000,000.0			$ 2,000,000.0					$ 2,000,000.0		4,000,000.0				$ 2,500,000
Eligible Number Of Indications | Indication																								3
Payments received in connection with additional indications																								$ 5,000,000.0
Potential payments received in connection with additional indications																								$ 335,000,000.0
Description of royalty percentage receivable on net sales																								The Company is also eligible to receive tiered double-digit royalties on net sales, if any, of licensed products in the EUSA Licensed Territories ranging from a low double digit up to mid-twenty percent depending on the level of annual net sales.
Collaborations and license agreements, potential future payment as percentage of certain amounts the Company receives under sublicense agreements																								30.00%
Total revenue recognized																								$ 900,000		800,000
Deferred revenue recognized as collaboration and licensing revenue																								2,100,000
Deferred revenue continue to be recognized as collaboration and licensing revenue per quarter																								500,000
EUSA | Partnership Royalties
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Sales royalties revenue recognized																								400,000		300,000
EUSA | Milestone - UK Reimbursement Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Allocation of upfront payment												$ 600,000
Collaborations and license agreements, expected milestone receivable													$ 2,000,000.0
EUSA | Milestone - German Reimbursement Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Allocation of upfront payment							$ 600,000
Collaborations and license agreements, expected milestone receivable								$ 2,000,000.0
EUSA | Milestone Spain Reimbursement Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Allocation of upfront payment				$ 600,000
Collaborations and license agreements, expected milestone receivable					$ 2,000,000.0
EUSA | Opt In To Planned Phase Three Study
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment to be received																								20,000,000.0
EUSA | Marketing Approval in France, Germany, Italy, Spain and the United Kingdom
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment to be received																								2,000,000.0
EUSA | Marketing Approval in Australia, Brazil, New Zealand, South Africa and Switzerland
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment to be received																								2,000,000.0
EUSA | Opt-in to Co-develop TiNivo Trial
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable																$ 2,000,000.0
EUSA | TiNivo trial
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement received															$ 2,000,000.0
Biodesix
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Trade receivables, net																								200,000
Amounts due from pursuant to the cost-sharing provisions																								200,000
Biodesix | FOCAL study | Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contribution percentage of clinical, regulatory, manufacturing and other costs																															50.00%
Biodesix | FOCAL trial
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, royalties payment on revenue																															2500.00%
Payments received and recorded as an increased (decreased) to expense pursuant to cost-sharing provisions																								100,000		600,000
Biogen Idec International GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Allocation of upfront payment										$ 700,000
Biogen Idec International GmbH | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty payments																								$ 50,000,000.0
Biogen Idec International GmbH | Licensing Agreements | Development and Regulatory Milestone Events
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and licensing revenue											$ 2,000,000.0
St Vincent's Hospital Sydney Limited
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amendment agreement date																								2015-08
St Vincent's Hospital Sydney Limited | Development and Regulatory Milestone Events | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognition milestone method milestone payables																								$ 14,400,000
St Vincent's Hospital Sydney Limited | Licensing Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received																								1,500,000
Kyowa Kirin
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone Payment																								0
Kyowa Kirin | Licensing Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received																								$ 5,000,000.0
Upfront payment receivable			$ 25,000,000.0
Collaborations and license agreements, one time milestone payment waived																														$ 18,000,000.0
Collaborations and license agreements, milestone payment																						$ 10,000,000.0
Kyowa Kirin
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and licensing revenue		$ 2,800,000
Non refundable upfront payment			$ 25,000,000.0
Revenues																									$ 2,800,000		$ 25,000,000.0
Transaction price																									$ 27,800,000
Kyowa Kirin | Opt In To Planned Phase Three Study | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement potential opt-in payment																							$ 20,000,000.0
Kyowa Kirin | Licensing Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, potential future payment as percentage of certain amounts the Company receives under sublicense agreements																								30.00%
Collaborations and license agreements, one time milestone payment waived																								$ 18,000.0
Term of royalty payment obligations																							12 years	10 years
Royalties on the net sales																								$ 100,000
Collaborations and license agreements, expected milestone receivable																								390,700,000
Non refundable upfront payment																								25,000,000.0
Kyowa Kirin | Licensing Agreements | FDA Marketing Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, milestone payment																					$ 12,000,000.0
Kyowa Kirin | Licensing Agreements | IND Marketing Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and licensing revenue	$ 2,800,000
Research and development | Astra Zeneca Inc. | Astra Zeneca Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received and recorded as an increased (decreased) to expense pursuant to cost-sharing provisions																								$ 200,000		$ 400,000