Aggregate amount of milestone payments.

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Collaborative Arrangement, Percentage of Development Costs Incurred

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- Definition

Contingent Consideration Receivable

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Forfeiture of Remaining Rights and Payment of Cost, Penalty Percentage

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Future Opt-In Payment Eligible To Receive Under Collaboration Arrangement

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Nonrefundable Upfront Payment

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Revenue Recognition, Multiple-deliverable Arrangements, Amount

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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, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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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 deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Janssen Collaboration Agreement (Details) - USD ($)		3 Months Ended			9 Months Ended
Janssen Collaboration Agreement (Details) - USD ($)	Jul. 13, 2017	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License and collaboration revenue - related party			$ 8,781,000	$ 0	$ 8,781,000	$ 0
Deferred revenue - related party			41,739,000		41,739,000			$ 0
Receivable from collaboration partner - related party			520,000		520,000			0
Change in Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Asset, Net			520,000		520,000		$ 0	0
Contract with Customer, Asset, Period Increase			520,000		520,000
Contract with Customer, Liability			41,739,000		41,739,000		$ 0	$ 0
Contract with Customer, Liability, Period Increase			50,000,000		50,132,000
Contract with Customer, Liability, Revenue Recognized			(8,261,000)		(8,393,000)
Janssen Biotech, Inc. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
License and collaboration revenue - related party			$ 400,000		$ 400,000
Collaborative Arrangement, Product [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative arrangement, percentage of development costs incurred			20.00%		20.00%
Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Nonrefundable upfront payment	$ 50,000,000
Collaborative arrangement, percentage of development costs incurred			80.00%		80.00%
License and collaboration revenue - related party			$ 8,800,000		$ 8,800,000
Revenue recognition, amount			8,400,000		8,400,000
Deferred revenue - related party			100,000		100,000
Change in Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Asset, Net			54,200,000		54,200,000
Contract with Customer, Liability, Revenue Recognized					8,400,000
Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent consideration receivable		$ 25,000,000
Collaboration agreement, detail capital required for commercial launch, percent (up to)		30.00%
First Opt-in [Member] \| Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Forfeiture of remaining rights and payment of cost, penalty percentage		50.00%
Future opt-in payment eligible to receive under collaboration arrangement		$ 125,000,000
Second Opt-in [Member] \| Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Future opt-in payment eligible to receive under collaboration arrangement		200,000,000
Aggregate milestone payment		590,000,000
Deferred Revenue [Member] \| Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Deferred revenue - related party			$ 41,700,000		$ 41,700,000
Cost-Sharing Payments [Member] \| Collaborative Arrangement, Product [Member] \| Janssen Biotech, Inc. [Member] \| Scenario, Forecast [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contingent consideration receivable		$ 4,200,000