|
Commitments and Contingencies - Additional Information (Detail) (USD $)
|
12 Months Ended | 1 Months Ended | 9 Months Ended | 12 Months Ended | ||||
|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2012
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Jul. 31, 2011
South San Francisco California [Member]
sqft
|
Sep. 30, 2011
Headquarters [Member]
Redwood City, California [Member]
Lease and Sublease [Member]
sqft
|
Sep. 30, 2011
Headquarters [Member]
Redwood City, California [Member]
Sublease Agreement [Member]
|
Sep. 30, 2011
Headquarters [Member]
Redwood City, California [Member]
Lease agreement [Member]
|
Dec. 31, 2012
Research Laboratories [Member]
Redwood City, California [Member]
Lease agreement [Member]
sqft
|
|
| Commitments And Contingencies [Line Items] | ||||||||
| Square feet of laboratory space and/or office space | 28,180 | 67,905 | 6,489 | |||||
| Lease agreement expiration date | Apr. 30, 2017 | Feb. 28, 2010 | Sep. 30, 2011 | Aug. 31, 2012 | ||||
| Aggregate rent over life of lease | $ 3,400,000 | |||||||
| Security deposit for lease | 60,000 | |||||||
| Rent expense | 700,000 | 1,300,000 | 1,200,000 | |||||
| Purchase commitments | $ 4,600,000 | |||||||