Major Customers, Partnerships and Strategic Alliances - Revenues Recognized under Agreement (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Shire AG [Member]
Revenue related to Biogen Collaboration:
Recognition of upfront fee	$ 542	$ 542
Research services	4,979	3,214
Total	5,521	3,756
Revenue related to Sigma Collaboration:
Royalty revenues	0
Total	5,521	3,756
Sigma-Aldrich Corporation [Member]
Revenue related to Biogen Collaboration:
Total	285	314
Revenue related to Sigma Collaboration:
Royalty revenues	106	314
License fee and milestone revenues	179
Total	285	314
Biogen [Member]
Revenue related to Biogen Collaboration:
Recognition of upfront fee	660
Research services	423
Total	1,083
Revenue related to Sigma Collaboration:
Total	$ 1,083

Deferred upfront contract fee revenue.

No definition available.

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- Definition

Research service revenue under collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product.

+ References

+ Details

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- Definition

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

+ References

+ Details

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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