v3.22.2.2
Commitments and contingencies - Narrative (Details) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended
Apr. 29, 2020
Aug. 31, 2021
Dec. 31, 2019
May 31, 2019
Aug. 31, 2018
Sep. 30, 2022
Jun. 30, 2016
Sep. 30, 2022
Jul. 31, 2022
Dec. 31, 2021
May 29, 2020
Other Commitments                      
Milestone payable           $ 50,000   $ 50,000      
Accrued royalties           41,897   41,897   $ 35,679  
Wellcome Trust                      
Other Commitments                      
Development milestone payment obligations           7,000   7,000      
Milestone obligation payments made             $ 800        
Wellcome Trust | Other long-term liabilities                      
Other Commitments                      
Development milestone payment obligations           4,500   4,500      
Wellcome Trust | Accounts payable and accrued expenses                      
Other Commitments                      
Development milestone payment obligations           2,500   2,500      
Akcea                      
Other Commitments                      
Upfront licensing fee         $ 12,000            
Milestone payments   $ 4,000                  
Akcea | Maximum                      
Other Commitments                      
Milestone payments   $ 4,000                  
Censa                      
Other Commitments                      
Asset acquisition, development and regulatory milestones                     $ 109,000
Asset acquisition, initial milestone                     30,000
Censa | Maximum                      
Other Commitments                      
Asset acquisition, milestone, amount                     217,500
Asset acquisition, net sales milestone                     $ 160,000
Agilis Merger Agreement | Akcea                      
Other Commitments                      
Milestone payments     $ 4,000 $ 6,000              
SMA License Agreement | SMA Foundation                      
Other Commitments                      
Royalty expense               24,500      
Royalty payments               12,100      
Accrued royalties           12,400   12,400      
SMA License Agreement | SMA Foundation | Maximum                      
Other Commitments                      
Potential royalty payments due on net product sales               52,500      
Agilis                      
Other Commitments                      
Development milestone payment obligations                 $ 50,000    
Development milestone payments which the entity is obligated to pay $ 40,000         40,000   40,000      
Reduction in contingent consideration payable           $ 50,000          
Development milestone obligation payments made               $ 2,400      
Agilis | Minimum                      
Other Commitments                      
Product sales (as a percent)           2.00%   2.00%      
Agilis | Maximum                      
Other Commitments                      
Development milestone payments which the entity is obligated to pay           $ 60,000   $ 60,000      
Priority review voucher amount               535,000      
Net sales amount           $ 150,000   $ 150,000      
Product sales (as a percent)           6.00%   6.00%      
Development milestone payment obligations, net of cancellation and forfeiture               $ 20,000      
Contingent liability, milestone, potential achievements, priority review voucher amount, net of cancellation and forfeiture               361,000      
Agilis | Accounts payable and accrued expenses                      
Other Commitments                      
Milestone payable           $ 50,000   50,000      
Agilis | Rights Exchange Agreement                      
Other Commitments                      
Contingent liability cancellation and forfeiture of potential milestone payments 174,000                    
Development milestone payment obligations, cancellation and forfeiture 37,600                    
Contingent liability, cancellation and forfeiture $ 211,600                    
BioElectron | Maximum                      
Other Commitments                      
Development milestone payments which the entity is obligated to pay           200,000   200,000      
Marathon | Agilis Merger Agreement                      
Other Commitments                      
Milestone obligation payments made               50,000      
Net product revenue | Wellcome Trust | Maximum                      
Other Commitments                      
Development milestone payments which the entity is obligated to pay           $ 10,000   $ 10,000