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Represents the initial period of the collaborative agreement.

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No definition available.

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Represents the estimated utilization period after commercialization of the product, which is used to allocate fees to the deliverables in the contract.

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No definition available.

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Represents the term of extension of the collaborative agreement.

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Represents the estimated term of licenses under the collaborative arrangements.

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No definition available.

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Represents the number of single-target licenses the company has right to use.

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No definition available.

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Represents the potential payment to extend the term of the collaborative agreement.

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Represents the potential payments to expand the scope of the collaborative agreement.

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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.

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No definition available.

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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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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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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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Agreements - Takeda (Details)	1 Months Ended	3 Months Ended										6 Months Ended		12 Months Ended			22 Months Ended
Agreements - Takeda (Details)	Mar. 31, 2015 USD ($) item	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2016 USD ($)
Collaborative Agreements disclosures
Amount of arrangement consideration included in license and milestone fees		$ 5,076,000	$ 76,000	$ 76,000	$ 10,077,000	$ 10,692,000	$ 6,070,000	$ 5,086,000	$ 5,078,000	$ 41,417,000	$ 6,234,000	$ 5,152,000	$ 16,762,000	$ 26,915,000	$ 57,815,000	$ 39,455,000
Costs related to the research and development services		33,657,000	$ 32,909,000	$ 38,652,000	$ 36,094,000	$ 38,199,000	$ 35,132,000	$ 30,437,000	25,666,000	$ 27,647,000	$ 28,018,000	$ 66,566,000	73,331,000	148,077,000	111,768,000	106,958,000
Takeda
Collaborative Agreements disclosures
Number of single-target licenses \| item	2											1
Term of agreement	3 years
Term of extension of the agreement	1 year
Potential payments to extend the agreement term	$ 4,000,000
Potential payment to expand agreement scope	8,000,000
Payments received under collaboration agreement	20,000,000																$ 31,400,000
Potential milestone payments	$ 210,000,000								210,000,000
Additional term of extension of the agreement	2 years
Estimated utilization period after commercialization	10 years
Discount rate (as a percent)	13.00%
Amount of arrangement consideration included in license and milestone fees														8,600,000
Estimated term of development and commercialization license	25 years
Remaining arrangement consideration to be recognized as license revenue		17,300,000										$ 17,300,000					17,300,000
Costs related to the research and development services												678,000		$ 469,000	$ 113,000	$ 0
Takeda \| Development milestones
Collaborative Agreements disclosures
Payments received under collaboration agreement																	25,900,000
Potential milestone payments	$ 30,000,000								30,000,000
Takeda \| Phase I clinical trial
Collaborative Agreements disclosures
Potential milestone payments		$ 5,000,000										$ 5,000,000					5,000,000
Takeda \| Regulatory milestones
Collaborative Agreements disclosures
Potential milestone payments	85,000,000								85,000,000
Takeda \| Sales milestones
Collaborative Agreements disclosures
Potential milestone payments	$ 95,000,000								$ 95,000,000
Takeda \| Future Technological Improvements
Collaborative Agreements disclosures
Payments received under collaboration agreement													$ 2,100,000
Takeda \| Research Services
Collaborative Agreements disclosures
Payments received under collaboration agreement																	$ 3,400,000