v2.4.0.8
Tax Effects of Temporary Differences Comprise Deferred Tax Assets and Liabilities (Detail) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Deferred tax assets        
Equity securities   $ 4,346 $ 1,098  
Accrued liabilities   1,910 915  
Stock-based compensation   363 178  
Deferred revenue   22,684 6,546  
Research and development tax credits 6,600 5,848 5,556  
Net operating loss carryforwards   80,159 70,679  
Total deferred tax assets   115,310 84,972  
Less: Valuation allowance   113,051 82,125 52,036
Net deferred tax assets   2,259 2,847  
Deferred tax liabilities        
Property and equipment   478 406  
Intangible assets   1,781 2,441  
Total deferred tax liabilities   2,259 2,847  
Net deferred tax assets (liabilities)