v3.26.1
INCOME TAXES - Schedule of Reconciliation Between Statutory Federal Income Tax Rate and Effective Income Tax Rate - After the adoption of ASU 2023-09 (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount        
Federal statutory rate $ 19,587   $ 27,920  
State income taxes, net of federal tax effect 1,501   $ 2,017  
Effective Income Tax Rate Reconciliation, State and Local Jurisdiction, Contribution Greater than 50 Percent, Tax Effect [Extensible Enumeration]     stpr:IL  
Tax credits        
Orphan drug credit (3,060)   $ (4,322)  
Research and development credit (770)   (1,080)  
Other nontaxable or nondeductible items 742   664  
Other adjustments (166)   (166)  
Income Tax Expense (Benefit), Total $ 17,834 $ 9,861 $ 25,033 $ 21,478
Tax Jurisdiction of Domicile [Extensible Enumeration] UNITED STATES   UNITED STATES  
Effective Income Tax Rate Reconciliation, Percent        
Federal statutory rate 21.00% 21.00% 21.00% 21.00%
State income taxes, net of federal tax effect 1.60% 1.30% 1.50% 1.20%
Tax credits        
Orphan drug credit (3.30%)   (3.30%)  
Research and development credit (0.80%)   (0.80%)  
Other nontaxable or nondeductible items 0.80%   0.50%  
Other adjustments (0.20%) 0.60% (0.10%) 0.40%
Effective tax rate 19.10% 19.90% 18.80% 20.10%