Asset acquisition.

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Collaborative arrangement profit share percentage.

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Finite lived intangible assets amortization expense after year four.

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Milestone payable on achievement of certain events.

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Milestone payment.

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Notice period for agreement termination.

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- Definition

Percentage of royalty obligated to pay under agreement.

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- Definition

Percentage of royalty on product sales.

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No definition available.

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- Definition

Research and development milestone obligation to be paid.

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No definition available.

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- Definition

Variable Interest entity upfront payments.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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- Definition

Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

+ References

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- Definition

The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
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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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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Description of the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, that could require the reporting entity to provide financial support (for example, liquidity arrangements and obligations to purchase assets) to the Variable Interest Entity (VIE), including events or circumstances that could expose the reporting entity to a loss.

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Asset Acquisition and License Agreements - Additional Information (Detail) - USD ($)	1 Months Ended				3 Months Ended								12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2010
Asset Acquisition [Line Items]
Restricted cash (SRX Cardio)					$ 1,062,000				$ 173,000				$ 1,062,000	$ 173,000
Net Income (loss) attributable to noncontrolling interest (SRX Cardio)					(338,000)	$ 126,000	$ 223,000	$ (332,000)	280,000	$ (5,000)	$ 240,000	$ (45,000)	(321,000)	470,000	$ 930,000
Milestone payment on regulatory approval														5,000,000
Research and development expense													216,205,000	203,701,000	246,854,000
Millennium
Asset Acquisition [Line Items]
2019					600,000								600,000
2020					600,000								600,000
2021					600,000								600,000
2022					600,000								600,000
Thereafter					1,800,000								1,800,000
Millennium \| United States
Asset Acquisition [Line Items]
Milestone payment on regulatory approval	$ 5,000,000
Millennium \| Research and Development Expense
Asset Acquisition [Line Items]
Milestone payment		$ 2,000,000
Millennium \| Cost of Sales \| United States
Asset Acquisition [Line Items]
Finite-lived intangible assets, amortization expense													600,000
Astellas Pharma Inc
Asset Acquisition [Line Items]
Percentage required to pay for any payment received under collaboration excluding royalties																20.00%
Research and development expense													$ 0	800,000	1,800,000
Maximum \| Millennium
Asset Acquisition [Line Items]
Percentage of royalty on product sales													8.00%
Maximum \| Astellas Pharma Inc
Asset Acquisition [Line Items]
Milestone payable on occurrence of specified events																$ 71,500,000
Minimum \| Millennium
Asset Acquisition [Line Items]
Percentage of royalty on product sales													2.00%
SRX Cardio
Asset Acquisition [Line Items]
Variable interest entity, Upfront payment			$ 2,200,000	$ 500,000
Variable interest entity, Terms of arrangements													Accordingly, SRX Cardio is subject to consolidation and we have consolidated the financial statements of SRX Cardio by (a) eliminating all intercompany balances and transactions; and (b) allocating income or loss attributable to the noncontrolling interest in SRX Cardio to net income or loss attributable to noncontrolling interest in our consolidated statement of operations and reflecting noncontrolling interest on our consolidated balance sheet.
Fair value of indefinite lived intangible assets					3,200,000								$ 3,200,000
Noncontrolling interest in variable Interest entity					2,900,000								2,900,000
Restricted cash (SRX Cardio)		$ 178,000			$ 30,000				$ 173,000				$ 30,000	$ 173,000	$ 178,000
SRX Cardio \| License Agreement
Asset Acquisition [Line Items]
Notice period for agreement termination			90 days
SRX Cardio \| License Agreement \| Maximum
Asset Acquisition [Line Items]
Research and development milestone payment obligation			$ 152,500,000
Percentage of royalties on worldwide net sales, obligated to pay			6.00%
SRX Cardio \| License Agreement \| Minimum
Asset Acquisition [Line Items]
Percentage of royalties on worldwide net sales, obligated to pay			2.00%