Revenue Recognition - Estimated Revenue Expected to be Recognized in Future Related to Performance Obligations (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction Price Allocated to the Remaining Performance Obligation as of September 30, 2019	$ 4,423
Bristol-Myers Squibb Company (BMS) and Pfizer Inc. (Pfizer) \| 2016 Agreement
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction Price Allocated to the Remaining Performance Obligation as of September 30, 2019	$ 382
Expected Year By Which Revenue Recognition Will Be Completed	2021
Percentage of Revenue Recognized	97.00%
Daiichi Sankyo, Inc ("Daiichi") \| 2016 Agreement
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction Price Allocated to the Remaining Performance Obligation as of September 30, 2019	$ 1,969
Expected Year By Which Revenue Recognition Will Be Completed	2025
Percentage of Revenue Recognized	88.00%
Daiichi Sankyo, Inc ("Daiichi") \| 2014 Agreement
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction Price Allocated to the Remaining Performance Obligation as of September 30, 2019	$ 600
Expected Year By Which Revenue Recognition Will Be Completed	2021
Percentage of Revenue Recognized	98.00%
Bayer Pharma AG \| 2016 Agreement
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Transaction Price Allocated to the Remaining Performance Obligation as of September 30, 2019	$ 1,472
Expected Year By Which Revenue Recognition Will Be Completed	2025
Percentage of Revenue Recognized	91.00%

Percentage of revenue recognized.

No definition available.

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

+ Details

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- Definition

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+ References

No definition available.

+ Details

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- Definition

Year in which remaining performance obligation is expected to be recognized, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

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