The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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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The amount of consideration recognized during the period for the milestone or milestones.

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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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-SubTopic 28
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Aggregate carrying amount, as of the balance sheet date, of noncurrent note payable for upfront fee. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

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Proceeds from upfront fee.

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Collaboration Agreements (Details) CAD in Thousands, $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CAD	Dec. 31, 2014 USD ($)	Dec. 31, 2014 CAD	Dec. 31, 2013 USD ($)	Dec. 31, 2013 CAD	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Nov. 30, 2010 USD ($)
Collaboration Agreements [Line Items]
Upfront payment performance description		The Company determined that the $1,500 upfront payment should be recognized as revenue ratably over the expected period of performance, being the two-year period ending March 18, 2016	The Company determined that the $1,500 upfront payment should be recognized as revenue ratably over the expected period of performance, being the two-year period ending March 18, 2016
Research and development		$ 15,152		$ 11,768		$ 12,303
Sales Based Milestone
Collaboration Agreements [Line Items]
Proceeds from milestone payments		0
uniQure [Member]
Collaboration Agreements [Line Items]
Proceeds from milestone payments \| CAD			CAD 0		CAD 0		CAD 547
uniQure [Member] \| Glybera [Member]
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable \| CAD			CAD 1,000
Teva [Member]
Collaboration Agreements [Line Items]
Proceeds from milestone payments		0
Potential Milestone Payments Receivable								$ 335,000
Teva [Member] \| Clinical Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable								20,000
Teva [Member] \| Regulatory Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable								285,000
Teva [Member] \| Sales Based Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable								30,000
Teva [Member] \| TV-45070 [Member]
Collaboration Agreements [Line Items]
Proceeds from upfront fee								$ 41,000
Genentech [Member]
Collaboration Agreements [Line Items]
Proceeds from milestone payments		250		0
Potential Milestone Payments Receivable	$ 1,750								$ 613,000
Proceeds from upfront fee	1,500
Genentech [Member] \| Regulatory Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable									387,500
Genentech [Member] \| Sales Based Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable									180,000
Genentech [Member] \| Preclinical And Clinical Milestone
Collaboration Agreements [Line Items]
Potential Milestone Payments Receivable									45,500
Genentech [Member] \| Preclinical Clinical and Regulatory Milestones
Collaboration Agreements [Line Items]
Proceeds from milestone payments		$ 0		$ 8,000		5,000
Genentech [Member] \| GDC-0276 [Member]
Collaboration Agreements [Line Items]
Proceeds from upfront fee									$ 10,000
Genentech Affiliate [Member]
Collaboration Agreements [Line Items]
Proceeds from Issuance of Private Placement	$ 4,455
Ionis [Member]
Collaboration Agreements [Line Items]
Notes payable for upfront fee										$ 1,500
Research and development						$ 2,000