The minimum amount the entity agreed to spend for research funding under the collaboration agreement.

No definition available.

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- Definition

Period covered by the long-term collaboration agreement research funding commitment.

+ References

No definition available.

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- Definition

Collaboration agreement aggregate success payments.

+ References

No definition available.

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- Definition

Collaboration agreement success payments term.

+ References

No definition available.

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- Definition

Collaboration agreement term.

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No definition available.

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- Definition

Estimated fair value of the total success payment liability.

+ References

No definition available.

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- Definition

Multiple of equity value at issuance used in the calculation of potential success payments.

+ References

No definition available.

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- Definition

Success payment expense (gain).

+ References

No definition available.

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- Definition

Success payment liability recorded on the balance sheet.

+ References

No definition available.

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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-Publisher FASB

-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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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Amount per share or per unit of equity securities issued by non-development stage entity.

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Collaboration Agreements - Fred Hutchinson Cancer Research Center - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Oct. 31, 2013
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and development expenses	$ 57,799,000us-gaap_ResearchAndDevelopmentExpense	$ 2,939,000us-gaap_ResearchAndDevelopmentExpense
Estimated fair value of total success payment obligation	230,300,000		195,900,000
Success payment expense/gain	38,900,000juno_SuccessPaymentExpenseGain	200,000juno_SuccessPaymentExpenseGain
Success payment liability balance	123,830,000juno_SuccessPaymentLiability		84,920,000juno_SuccessPaymentLiability
Fred Hutchinson Cancer Research Center [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Per share common stock price required for payment	$ 60.66		52.22
Fred Hutchinson Cancer Research Center [Member] \| Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Risk free interest rate	1.63%		1.94%
Expected term (years)	6 years 6 months 18 days		6 years 9 months 15 days
Fred Hutchinson Cancer Research Center [Member] \| Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Risk free interest rate	1.91%		2.16%
Expected term (years)	9 years 6 months 18 days		9 years 9 months 15 days
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration agreement, term				6 years
Research and development expenses	2,000,000	500,000
Estimated fair value of total success payment obligation	162,900,000		139,100,000
Success payment expense/gain	27,200,000	100,000
Success payment liability balance	88,400,000		61,200,000
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Term of success payments	8 years
Risk free interest rate	1.63%
Expected term (years)	6 years 6 months 18 days
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate success payments	375,000,000
Term of success payments	11 years
Risk free interest rate	1.91%
Expected term (years)	9 years 6 months 18 days
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Common Stock [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Issuance of common stock price per share	$ 4.00
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Common Stock [Member] \| Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Multiple of Equity Value at issuance	5
Per share common stock price required for payment	$ 20.00
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Common Stock [Member] \| Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Multiple of Equity Value at issuance	40
Per share common stock price required for payment	$ 160.00
Collaborative Arrangement [Member] \| Fred Hutchinson Cancer Research Center [Member] \| Research and Development Arrangement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Aggregate research funding, committed	$ 9,300,000
Aggregate research funding, commitment period	6 years