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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The number of drugs that can be licensed by the partner(s) under their respective collaboration agreements.

+ References

No definition available.

+ Details

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- Definition

The number of obligations fully satisfied under the collaboration agreement for which revenue is recognized over the period of performance.

+ References

No definition available.

+ Details

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- Definition

Total payments received since inception of the collaboration agreement included in the transaction price for the performance obligation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The number of separate performance obligations under the collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The amount of upfront payments received during the period under the collaboration agreement.

+ References

No definition available.

+ Details

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Balance Type:	debit
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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, AstraZeneca (Details) $ in Thousands	1 Months Ended			3 Months Ended			6 Months Ended
	Dec. 31, 2016 USD ($)	Jul. 31, 2015 USD ($) PerformanceObligation Drug	Dec. 31, 2012 USD ($) PerformanceObligation	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2014 PerformanceObligation
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 117,747		$ 112,273	$ 262,165	$ 228,073
Deferred revenue									$ 233,362
Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				545		1,322	1,487	3,912
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				60,549		$ 88,585	162,944	$ 196,584
AstraZeneca [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue				$ 48,100			$ 48,100		$ 57,700
AstraZeneca [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage				3.00%		4.00%	28.00%	4.00%
AstraZeneca [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 3,900		$ 5,000	$ 72,300	$ 9,900
Cardiac, Renal and Metabolic Diseases [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs that can be licensed under option in collaboration agreements \| Drug		3
Upfront payment received		$ 65,000
Minimum amount of payments receivable for license fees and substantive milestones				4,000,000			4,000,000
Maximum amount of payments receivable for development milestones				1,100,000			1,100,000
Maximum amount of payments receivable for regulatory milestones				2,900,000			2,900,000
Cumulative payments received				155,000			155,000
Next prospective payment				10,000			10,000
Number of separate performance obligations \| PerformanceObligation		1
Transaction price		$ 65,000
Cardiac, Renal and Metabolic Diseases [Member] \| IONIS-AZ5-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue					$ 30,000
Cardiac, Renal and Metabolic Diseases [Member] \| IONIS-AZ6-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue					$ 30,000
Cardiac, Renal and Metabolic Diseases [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Payments included in transaction price for performance obligation				90,000			90,000
Oncology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received			$ 31,000
Minimum amount of payments receivable for license fees and substantive milestones				750,000			750,000
Maximum amount of payments receivable for development milestones				226,000			226,000
Maximum amount of payments receivable for regulatory milestones				485,000			485,000
Cumulative payments received				97,800			97,800
Next prospective payment				$ 17,500			$ 17,500
Number of separate performance obligations \| PerformanceObligation			4
Transaction price			$ 31,000
Number of obligations fully satisfied \| PerformanceObligation										3
Oncology [Member] \| IONIS-KRAS-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 13,000
Oncology [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price			$ 7,600