Collaborations and License Agreements - Additional Information (Detail)	1 Months Ended													3 Months Ended								6 Months Ended		12 Months Ended		25 Months Ended	27 Months Ended
	Feb. 28, 2018 USD ($)	Oct. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Feb. 28, 2017 USD ($)	Apr. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Aug. 31, 2015 USD ($)	Dec. 31, 2012 USD ($)	Mar. 31, 2010 USD ($)	Dec. 31, 2006 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2018 USD ($) Indication Installment	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Feb. 28, 2018 USD ($)	Jan. 31, 2019 USD ($)	Jan. 01, 2018 USD ($)	Oct. 14, 2016	Apr. 30, 2014 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															$ 433,000			$ 351,000				$ 1,459,000	$ 2,883,000
Accumulated deficit															(594,664,000)							(594,664,000)		$ (586,969,000)		$ (586,969,000)
Deferred revenue, current portion															1,342,000							1,342,000		395,000		395,000
Amounts due from pursuant to the cost-sharing provisions															973,000							973,000		402,000		402,000
Research and development															4,887,000			6,881,000				10,291,000	14,837,000
Scenario Forecast
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment to be received														$ 0
Collaborations and license agreements, milestone payment														$ 0
ASC 606
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accumulated deficit																													$ (589,680,000)
Deferred revenue, current portion																													1,027,000
ASC 606 | Adjustments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															237,000							(882,000)
Deferred revenue																													2,700,000
Accumulated deficit															(3,592,000)							(3,592,000)							(2,711,000)
Deferred revenue, current portion															947,000							947,000							632,000
Collaboration and Licensing Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															336,000			351,000				1,316,000	2,883,000
Collaboration and Licensing Revenue | ASC 606 | Adjustments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															237,000							(882,000)
Partnership Royalties
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															97,000							$ 143,000
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
CANbridge
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement date																						Mar. 16, 2016
Revenue recognized from reimbursement of manufacturing development activities			500,000	$ 500,000
Revenues																							500,000
CANbridge | Collaboration and Licensing Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues																				$ 1,000,000
CANbridge | Licensing Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable						$ 1,000,000
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
Collaborations and license agreements, time period from first commercial sale of certain product upon which the agreement expires																						10 years
Description of royalty percentage receivable on net sales																						Upon commercialization, the Company is eligible to receive a tiered royalty, with a percentage range in the low double-digits, on net sales of approved licensed products.
Upfront consideration received upon execution							$ 1,000,000
CANbridge | Licensing Agreements | Commercial Milestone Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable																						$ 90,000,000
CANbridge | Licensing Agreements | Development and Regulatory Milestone Events
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable																						2,000,000
Collaborations and license agreements, expected milestone receivable																						0
CANbridge | Licensing Agreements | Additional Development and Regulatory Milestone Events
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable																						$ 40,000,000
EUSA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable			4,000,000					$ 2,500,000
Collaborations and license agreements, expected milestone receivable	$ 2,000,000
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.
Revenues															$ 433,000			99,000				$ 1,459,000	198,000
Research and development reimbursement received			$ 4,000,000																			$ 6,500,000			$ 2,500,000
Percentage of additional proceeds from research and development funding																						50.00%
Payments received in connection with indications																						$ 2,000,000
Eligible number of indications | Indication																						3
Payments received in connection with additional indications																						$ 5,000,000
Potential payments received in connection with additional indications																						$ 335,000,000
Collaborations and license agreements, potential future payment as percentage of certain amounts the Company receives under sublicense agreements															30.00%							30.00%
Allocation of upfront payment	600,000
Revenue, Information Used to Allocate Transaction Price																						The Company evaluated the promised goods and services at the inception of the EUSA Agreement under ASC 606. Based on this evaluation, the Company determined that $6.5 million in research and development payments by EUSA, including the $2.5 million upfront consideration received upon the execution of the EUSA Agreement in December 2015 and the $4.0 million payment upon the receipt of marketing approval from the EMA for tivozanib (FOTIVDA) for the treatment of aRCC in August 2017, constituted the amount of the consideration that was included in the transaction price upon the adoption of ASC 606 on January 1, 2018 and attributed this amount to the Company’s single performance obligation.
Remaining performance obligation revenue expected to be recognized over month and year																						2022-04
Research and development payment recognized																	$ 4,000,000
Deferred revenue															$ 5,100,000							$ 5,100,000
Revenue recognized as collaboration and licensing revenue related to the cumulative catch-up																										1,300,000	$ 700,000
Transaction price																$ 8,500,000
Deferred revenue, current portion	$ 1,300,000																										$ 1,300,000
Total revenues															400,000			100,000				1,500,000	200,000
Deferred revenue continue to be recognized as collaboration and licensing revenue per quarter															300,000							300,000
EUSA | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received in connection with indications																						8,000,000
EUSA | Research and development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received and recorded as an increased (decreased) to expense pursuant to cost-sharing provisions																						1,300,000
EUSA | ASC 606
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															433,000							1,459,000
Deferred revenue															5,091,000							5,091,000		$ 4,408,000		$ 4,408,000
EUSA | ASC 606 | Adjustments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue																													2,700,000
Accumulated deficit																													$ (2,700,000)
EUSA | Partnership Royalties
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Sales royalties revenue recognized															97,000							143,000
EUSA | Partnership Royalties | ASC 606
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues															97,000							143,000
EUSA | Opt-in to Planned Phase Three Study
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment to be received															20,000,000							20,000,000
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							2,000,000
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							2,000,000
EUSA | TiNivo trial
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement received		$ 2,000,000
Collaborations and license agreements, deferred research and development reimbursements															700,000							700,000
EUSA | TiNivo trial | Research and development
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			0				500,000	0
Novartis
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, expected milestone receivable									$ 15,000,000													0
Revenues																		15,000					1,820,000
Reimbursable inventory										$ 3,500,000
Transaction price recognized at the time option exercised																						3,500,000
Research and development																						1,800,000
Novartis | Collaboration and Licensing Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues					$ 1,800,000														$ 1,800,000		$ 15,000,000
Biodesix
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amounts due from pursuant to the cost-sharing provisions															200,000							200,000
Biodesix | FOCAL study
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contribution percentage of clinical, regulatory, manufacturing and other costs																															50.00%
Percentage of closeout project cost																														50.00%
Biodesix | FOCAL study | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Funding																															$ 15,000,000
Biodesix | FOCAL trial
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, royalties payment on net sales																															10.00%
Biodesix | FOCAL trial | Research and development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received and recorded as an increased (decreased) to expense pursuant to cost-sharing provisions															44,000			(100,000)				200,000	200,000
Astellas Pharma Inc. | Astellas Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amounts due from pursuant to the cost-sharing provisions															400,000							400,000
Astellas Pharma Inc. | Astellas Agreement | Research and development
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received and recorded as an increased (decreased) to expense pursuant to cost-sharing provisions															100,000			$ 100,000				0	$ 0
Biogen Idec International GmbH | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty payments																						$ 50,000,000
St Vincent's Hospital Sydney Limited
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amendment agreement date																						2015-08
Time-based milestone obligation payment				$ 1,800,000
St Vincent's Hospital Sydney Limited | Scenario Forecast
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional time-based milestone obligation payable																												$ 2,300,000
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															$ 16,700,000							$ 16,700,000
St Vincent's Hospital Sydney Limited | Licensing Agreements | Up-front Payment Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, cash payment																						1,500,000
Kyowa Hakko Kirin | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement payment not required to be paid																						$ 20,000,000
Kyowa Hakko Kirin | Opt-in to Planned Phase Three Study | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development reimbursement payment not required to be paid													$ 20,000,000
Kyowa Hakko 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%							30.00%
Collaborations and license agreements, cash payment																						$ 5,000,000
Collaborations and license agreements, milestone payment												$ 10,000,000
Collaborations and license agreements, potential future milestone payments, maximum amount											$ 18,000,000
Term of royalty payment obligations													12 years
Kyowa Hakko Kirin | Licensing Agreements | FDA Marketing Approval
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaborations and license agreements, milestone payment											$ 12,000,000