Aggregate additional revenue recognition milestone method revenue achieved.

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- Definition

Aggregate additional revenue recognition milestone method revenue eligible to receive.

+ References

No definition available.

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- Definition

Aggregate number of gene targets.

+ References

No definition available.

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- Definition

Collaboration and license agreements number of products approved under agreement.

+ References

No definition available.

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- Definition

Initial research term of agreement.

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- Definition

Milestone payments received.

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No definition available.

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- Definition

Milestone revenue receivable.

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No definition available.

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- Definition

Number of additional gene targets.

+ References

No definition available.

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- Definition

Number of gene targets.

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No definition available.

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- Definition

Number of initial gene targets.

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No definition available.

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- Definition

Number of research program.

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No definition available.

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section A

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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Subparagraph (SX 210.9-03.10(3))
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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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-Name Accounting Standards Codification
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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.6-07.1(c))
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- Definition

The amount of consideration recognized during the period for the milestone or milestones.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 28
-Section 50
-Paragraph 2
-Subparagraph (e)
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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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Major Customers, Partnerships and Strategic Alliances - Additional Information (Detail)	1 Months Ended			12 Months Ended
	Jan. 31, 2014 USD ($) Program	Jun. 30, 2012 Targets	Jan. 31, 2012 USD ($) Targets	Dec. 31, 2015 USD ($) Product Targets	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 01, 2015 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of research programs \| Program	2
Research and development				$ 67,198,000	$ 56,974,000	$ 37,039,000
Biogen Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenues under agreement	$ 20,000,000
Potential amount eligible to receive for certain milestones	126,300,000
Potential amount to be funded for achievement of specified commercialized and sales milestones	167,500,000
Milestone revenue receivable	293,800,000
Milestone payments received				$ 0
Number of products approved \| Product				0
Royalty revenues				$ 0
Research program to develop laboratory research reagents				40 months
Deferred revenue				$ 8,600,000
Biogen Inc [Member] \| Sickle cell disease [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone revenue receivable	7,500,000
Biogen Inc [Member] \| Beta-thalassemia Project [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Milestone revenue receivable	$ 7,500,000
Research and development				6,500,000	5,200,000
Biogen Inc [Member] \| Other Projects [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development				$ 2,900,000	3,500,000
Shire AG [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Revenues under agreement			$ 13,000,000
Research program to develop laboratory research reagents				6 years
Deferred revenue				$ 5,100,000
Research and development				$ 13,500,000	21,100,000	$ 14,200,000
Aggregate number of gene targets \| Targets			7
Number of initial gene targets \| Targets			4
Number of gene targets \| Targets		5
Number of additional gene targets \| Targets		2		1
Recognition of milestone					$ 1,000,000
Amount of obligation related to reimbursement							$ 4,000,000
Revenue recognized related to prior obligations				$ 3,400,000