v3.26.1
Taxation - Narrative (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Taxation [Line Items]      
Percentage vote and value of subsidiaries included in the Group consolidated federal tax return 80.00% 80.00% 80.00%
Percentage vote and value of subsidiaries in the Group consolidated state tax return 50.00% 50.00% 50.00%
Income tax expense/(benefit) $ (842) $ (4,008) $ 30,525
Uncertain Tax Position      
Taxation [Line Items]      
Other provisions 1,208    
Federal - current      
Taxation [Line Items]      
Tax losses     13,681
Tax credits 272 238 1,396
Federal - current | Operating loss carryforwards not subject to expiration      
Taxation [Line Items]      
Tax losses 118,870    
Massachusetts      
Taxation [Line Items]      
Tax losses 376,066 125,322 $ 111,446
Gross Amount      
Taxation [Line Items]      
Deferred tax assets (liabilities), net, not recognized 378,806 282,280  
Tax losses 123,691 7,815  
Tax credits 272 238  
US      
Taxation [Line Items]      
Deferred tax assets (liabilities), net, not recognized $ 102,037 $ 75,746