Revenue - Additional Information (Detail)
3 Months Ended 6 Months Ended 1 Months Ended 3 Months Ended 6 Months Ended 1 Months Ended 3 Months Ended 6 Months Ended 1 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2014
USD ($)
Jun. 30, 2013
USD ($)
Jun. 30, 2014
USD ($)
Jun. 30, 2014
RUB
Jun. 30, 2013
USD ($)
Jun. 30, 2013
RUB
Dec. 31, 2013
Amgen, Inc. [Member]
Jan. 31, 2013
Amgen, Inc. [Member]
USD ($)
Jun. 30, 2014
Amgen, Inc. [Member]
USD ($)
Jun. 30, 2013
Amgen, Inc. [Member]
USD ($)
Jun. 30, 2014
Amgen, Inc. [Member]
USD ($)
Jun. 30, 2013
Amgen, Inc. [Member]
USD ($)
Mar. 31, 2013
Pfizer Inc. [Member]
USD ($)
Option
Jun. 30, 2014
Pfizer Inc. [Member]
USD ($)
Jun. 30, 2013
Pfizer Inc. [Member]
USD ($)
Jun. 30, 2014
Pfizer Inc. [Member]
USD ($)
Jun. 30, 2013
Pfizer Inc. [Member]
USD ($)
Apr. 30, 2013
AstraZeneca AB [Member]
USD ($)
Jun. 30, 2014
AstraZeneca AB [Member]
USD ($)
Jun. 30, 2013
AstraZeneca AB [Member]
USD ($)
Jun. 30, 2014
AstraZeneca AB [Member]
USD ($)
Jun. 30, 2013
AstraZeneca AB [Member]
USD ($)
Jun. 30, 2014
F. Hoffmann-La Roche Ltd [Member]
USD ($)
Jun. 30, 2014
F. Hoffmann-La Roche Ltd [Member]
USD ($)
Jun. 30, 2014
Russia [Member]
Ministry of Industry and Trade of Russian Federation [Member]
USD ($)
Jun. 30, 2013
Russia [Member]
Ministry of Industry and Trade of Russian Federation [Member]
USD ($)
Jun. 30, 2014
Russia [Member]
Ministry of Industry and Trade of Russian Federation [Member]
USD ($)
Jun. 30, 2013
Russia [Member]
Ministry of Industry and Trade of Russian Federation [Member]
USD ($)
Revenues [Line Items]                                                        
Total revenue     $ 300,000 12,000,000 $ 400,000 11,700,000                                            
Contract amount recognized 253,000 365,000 418,000   365,000                                       253,000 365,000 418,000 365,000
Company received upfront payment               5,000,000 800,000       4,000,000         4,000,000                    
Option exercise period             6 months           30 months                              
Reduction in net loss per share, basic and diluted                 $ 0.05                                      
Company recognized amount related to the research, option and license agreement                 807,000 918,000 819,000 2,300,000   26,000 673,000 87,000 673,000   1,400,000 564,000 2,700,000 564,000 0 0        
Company granted option                         2                              
Total contingent payments                         89,500,000         193,000,000                    
Additional contingent payments                         $ 110,000,000