Revenue Accounted for 10% or More of Total Revenues (Detail)	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2012 Novartis AG	Dec. 31, 2012 Novartis AG	Dec. 31, 2011 Novartis AG	Dec. 31, 2010 Novartis AG	Jun. 30, 2013 Bristol-Myers Squibb Company (BMS) and Pfizer Inc. (Pfizer)	Jun. 30, 2013 Bayer Pharma, AG (Bayer) and Janssen Pharmaceuticals, Inc. (Janssen)	Dec. 31, 2011 Merck	Dec. 31, 2010 Merck	Dec. 31, 2011 Biogen Idec
Concentration Risk [Line Items]
Percentage of major customers revenue accounted for 10% or more of total revenues	100.00%	97.00%	12.00%	24.00%	54.00%	43.00%	40.00%	76.00%	48.00%

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13537-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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