Revenue Recognized Under Sanofi Agreement (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Contract revenue:
Amortization of upfront fees	$ 5,630	$ 18,977	$ 15,393
Reimbursement for development-related activities	468	1,278	2,319
Total contract revenue	$ 6,098	$ 20,255	$ 17,712

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

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)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 45

-Section 45

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21915142&loc=d3e60722-111653

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