No definition available.

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Cumulative amount of milestone payments, license fees and equity investment received under the collaborative arrangement as of the end of the reporting period.

+ References

No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date 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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-Publisher SEC
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The cash inflow from the additional capital contribution to the entity.

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-Publisher FASB
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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Collaborative Arrangements and Licensing Agreements, Research, Development and Commercialization Partners - Genzyme Corporation (Details) - USD ($)	1 Months Ended	3 Months Ended								12 Months Ended
	Jan. 31, 2008	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Collaborative Arrangement and Licensing Agreement [Abstract]
Equity investment in common stock										$ 0	$ 0	$ 173,292,000
Revenue earned		$ 51,571,000	$ 49,121,000	$ 120,428,000	$ 62,583,000	$ 84,861,000	$ 44,063,000	$ 57,076,000	$ 28,161,000	283,703,000	214,161,000	147,285,000
Genzyme Corporation [Member] \| Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recorded as deferred revenue	$ 175,000,000
Equity investment in common stock	$ 150,000,000
Cumulative payments, fees and equity investment received		$ 375,000,000								375,000,000
Revenue earned										$ 0	$ 0	$ 32,500,000
Genzyme Corporation [Member] \| Collaborations and Licensing Agreements [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage												22.00%