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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 maximum amount of payments receivable for commercialization milestones under the collaboration agreement.

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No definition available.

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The maximum amount of payments receivable for development milestones under the collaboration agreement.

+ References

No definition available.

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- Definition

The maximum amount of payments receivable for license fees and substantive milestones under the collaboration agreement.

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No definition available.

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- Definition

The maximum amount of payments receivable for regulatory milestones under the collaboration agreement.

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No definition available.

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

+ References

No definition available.

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- Definition

The number of antisense drugs in development designed to reduce the production of viral proteins associated with hepatitis B virus, or HBV, infection under the collaboration agreement.

+ References

No definition available.

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The number of separate performance obligations under the collaboration agreement.

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No definition available.

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The amount of consideration the Company is eligible to earn under the collaboration agreement, including any variable consideration.

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No definition available.

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The amount of upfront payments received during the period 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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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	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2010 USD ($) PerformanceObligation	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) Drug	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 117,747	$ 112,273	$ 262,165	$ 228,073
Deferred revenue						$ 233,362
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		60,549	$ 88,585	$ 162,944	$ 196,584
GSK [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received	$ 35,000
Number of antisense drugs in development \| Drug				2
Maximum amount of payments receivable for license fees and substantive milestones		262,000		$ 262,000
Maximum amount of payments receivable for development milestones		47,500		47,500
Maximum amount of payments receivable for regulatory milestones		120,000		120,000
Maximum amount of payments receivable for commercialization milestones		70,000		70,000
Next prospective milestone		15,000		15,000
Number of separate performance obligations \| PerformanceObligation	1
Transaction price	$ 35,000
Deferred revenue		$ 0		$ 0		$ 0
GSK [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		1.00%	3.00%	1.00%	4.00%
GSK [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received		$ 162,000		$ 162,000
GSK [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 1,300	$ 3,000	$ 1,400	$ 9,800