No definition available.

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- Definition

Cumulative amount of payments received under the collaboration agreement as of the end of the reporting period.

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No definition available.

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- Definition

The next potential milestone payment to be earned under the collaboration agreement.

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No definition available.

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The number of drugs currently being advanced under the collaboration agreement.

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

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

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Collaborative Arrangements and Licensing Agreements, GSK (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) Drug	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Drug	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 167,892	$ 145,395	$ 628,918	$ 407,559
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 72,193	$ 62,639	$ 376,833	$ 225,584
GSK [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs being advanced \| Drug	2		2
Next prospective milestone	$ 15,000		$ 15,000
Deferred revenue	$ 0		$ 0		$ 0
GSK [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	15.00%	0.00%	4.00%	0.00%
GSK [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received	$ 164,000		$ 164,000
GSK [Member] \| License Fees [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	25,000
GSK [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 25,100	$ 100	$ 25,300	$ 1,500