v3.26.1
Acquisitions - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 3 Months Ended 6 Months Ended
May 14, 2026
Jul. 02, 2024
Jun. 30, 2026
Apr. 29, 2026
Jan. 31, 2026
Nov. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
May 12, 2025
Business Combination [Line Items]                        
Goodwill     $ 6,990.8       $ 6,990.8   $ 6,990.8   $ 6,491.1  
Payments to acquire in process research and development                 135.0 $ 0.0    
TJ BIOPHARMA                        
Business Combination [Line Items]                        
Upfront and milestone paymentsmade to collaborative partner     225.0 $ 100.0                
Alcyone Therapeutics, Inc.                        
Business Combination [Line Items]                        
Payments to acquire productive assets   $ 85.0                    
Payments to acquire in process research and development         $ 35.0              
Asset acquisition, contingent consideration, range of outcomes, maximum, amount           $ 75.0            
Felzartamab | TJ BIOPHARMA | Milestone Payment, Commercial                        
Business Combination [Line Items]                        
Estimated additional payments upon achievement of development and commercial milestones       20.0                
Felzartamab | TJ BIOPHARMA | Milestone Payment, Sales-Based                        
Business Combination [Line Items]                        
Estimated additional payments upon achievement of development and commercial milestones       $ 730.0                
Felzartamab | TJ BIOPHARMA | Milestone Payment, Clinical And Regulatory                        
Business Combination [Line Items]                        
Estimated additional payments upon achievement of development and commercial milestones     $ 775.0       775.0   775.0      
Income Statement Location [Axis]: us-gaap:NetIncomeLoss                        
Business Combination [Line Items]                        
Share-based payment arrangement, expense             62.1 $ 60.0 129.6 125.0    
Income Statement Location [Axis]: us-gaap:ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCost                        
Business Combination [Line Items]                        
Share-based payment arrangement, expense             32.3 30.1 67.1 62.2    
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense                        
Business Combination [Line Items]                        
Share-based payment arrangement, expense             48.0 $ 48.0 101.0 $ 100.0    
Deferred tax liability                        
Business Combination [Line Items]                        
Debt instrument, face amount                       $ 1,750.0
Apellis Pharmaceuticals, Inc.                        
Business Combination [Line Items]                        
Price per share (in dollars per share) $ 41.00                      
Cash consideration paid to Apellis shareholders $ 5,406.0                      
Payment to shareholder (in dollars per share) $ 4.00                      
Outstanding unvested equity awards into cash retention awards $ 416.3                      
Pre-acquisition services 70.7                      
Contingent consideration 4.1                      
Share-based payment arrangement, expense 116.0                      
Inventory $ 712.0                      
Weighted-average amortization period 3 years                      
Discount rate 13.25%                      
Goodwill $ 501.5                      
Acquisition-related cost, expensed             $ 27.0   $ 30.8      
Business Combination, Separately Recognized Transaction, Acquisition-Related Cost, Expensed, Statement of Income or Comprehensive Income [Extensible Enumeration]             Selling, general and administrative   Selling, general and administrative      
Apellis Pharmaceuticals, Inc. | Completed Technology                        
Business Combination [Line Items]                        
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived 4,630.0                      
Apellis Pharmaceuticals, Inc. | EMPAVELI | Completed Technology                        
Business Combination [Line Items]                        
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived 2,400.0                      
Apellis Pharmaceuticals, Inc. | SYFOVRE | Completed Technology                        
Business Combination [Line Items]                        
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived 1,900.0                      
Apellis Pharmaceuticals, Inc. | Sobi | Royalty and other revenue                        
Business Combination [Line Items]                        
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived 380.0                      
Apellis Pharmaceuticals, Inc. | Pegcetacoplan | In-process research and development                        
Business Combination [Line Items]                        
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived 12.5                      
Apellis Pharmaceuticals, Inc. | Deferred tax liability                        
Business Combination [Line Items]                        
Debt instrument, face amount                       395.2
Apellis Pharmaceuticals, Inc. | Other, net                        
Business Combination [Line Items]                        
Debt instrument, face amount                       $ 101.5
Apellis Pharmaceuticals, Inc. | Secured Debt | Line of Credit                        
Business Combination [Line Items]                        
Contingent consideration 2,000.0                      
Debt instrument, face amount 400.0                      
Apellis Pharmaceuticals, Inc. | Previously Reported                        
Business Combination [Line Items]                        
Cash consideration paid to Apellis shareholders 5,300.0                      
Outstanding compensation expense $ 345.6