Revenue Accounted for 10% or More of Total Collaboration and License Revenues (Detail) - Customer Concentration Risk - Sales Revenue, Net	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Bayer Pharma, AG ('Bayer") and Janssen Pharmaceuticals, Inc. ("Janssen")
Concentration Risk [Line Items]
Concentration risk percentage	48.00%	37.00%	37.00%
Daiichi Sankyo, Inc ("Daiichi")
Concentration Risk [Line Items]
Concentration risk percentage	38.00%	45.00%	23.00%
Bristol-Myers Squibb Company ("BMS") and Pfizer Inc. ("Pfizer")
Concentration Risk [Line Items]
Concentration risk percentage	13.00%	16.00%	38.00%

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 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

Reference 4: 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=49121117&loc=d3e13537-108611

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