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Contract with customer liability revenue recognized from commercialization milestones.

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Revenue from contract with customer application input method.

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- Definition

Revenue recognition potential commercial milestone payments eligible upon successful commercialization.

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Revenue recognition transaction price.

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Right to terminate agreement if breach remains uncured.

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Right to terminate agreement incase of nonpayment.

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- Definition

Upfront fee recognized as revenue.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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Collaboration Agreement - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended			12 Months Ended
	Jul. 31, 2019	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Jun. 30, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development		$ 8,764		$ 3,921	$ 15,434		$ 7,367
License and Collaboration Agreement \| Astellas Pharma LLC
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement	$ 80,000
Agreement termination notice period	60 days
Right to terminate agreement if breach remains uncured	90 days
Right to terminate agreement incase of nonpayment	45 days
Transaction price allocated to single combined performance obligation					80,000
Accrued upfront payment related to sub License revenue		16,000			16,000			$ 16,000
Royalty			$ 16,000
Upfront fee recognized as revenue						$ 80,000
Revenue from contract with customer application input method		8,500			15,800			$ 44,700
Research and development		$ 337			$ 681
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 2b Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	$ 65,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 2b Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	25,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 3 Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	100,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 3 Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	40,000
License and Collaboration Agreement \| Maximum \| Astellas Pharma LLC
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	230,000
Revenue recognized commercialization milestone payments to receive	315,000
Potential commercial milestone payments eligible to receive upon successful commercialization	$ 315,000