Asset acquisition.

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- Definition

Collaborative arrangement profit share percentage.

+ References

No definition available.

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- Definition

Gain on derecognition of contingent milestone payable.

+ References

No definition available.

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- Definition

Milestone payable on achievement of certain events.

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No definition available.

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- Definition

Variable Interest entity upfront payments.

+ References

No definition available.

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- Definition

Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

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Asset Acquisition and License Agreements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2015	Dec. 31, 2010
Asset Acquisition [Line Items]
Impairment charge of intangible asset	$ 3,151,000	$ 0	$ 0
Research and development expense	124,627,000	216,205,000	$ 203,701,000
Astellas Pharma Inc
Asset Acquisition [Line Items]
Percentage required to pay for any payment received under collaboration excluding royalties			20.00%		20.00%
Research and development expense	0	$ 800,000	$ 1,800,000
Maximum \| Astellas Pharma Inc
Asset Acquisition [Line Items]
Milestone payable on occurrence of specified events					$ 71,500,000
SRX Cardio
Asset Acquisition [Line Items]
Variable interest entity, Upfront payment				$ 500,000
Gain on de-recognition of contingent milestone payable	2,300,000
Loss from deconsolidation	76,000
SRX Cardio \| In-process Research and Development
Asset Acquisition [Line Items]
Impairment charge of intangible asset	$ 3,200,000