v3.26.3
FINANCIAL INSTRUMENTS - Available-for-Sale Debt Securities in a Continuous Unrealized Loss Position (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Unrealized losses less than 12 months, fair value $ 3,754.4 $ 342.5
Unrealized losses less than 12 months, gross unrealized losses (59.5) (0.3)
Unrealized losses more than 12 months, fair value 54.8 267.2
Unrealized losses more than 12 months, gross unrealized losses (0.2) (1.4)
Total unrealized losses, fair value 3,809.2 609.7
Total unrealized losses, gross unrealized losses (59.7) (1.7)
U.S. treasuries    
Debt Securities, Available-for-sale [Line Items]    
Unrealized losses less than 12 months, fair value 3,198.5 298.0
Unrealized losses less than 12 months, gross unrealized losses (45.6) (0.3)
Unrealized losses more than 12 months, fair value 40.0 164.4
Unrealized losses more than 12 months, gross unrealized losses (0.1) (0.6)
Total unrealized losses, fair value 3,238.5 462.4
Total unrealized losses, gross unrealized losses (45.7) (0.9)
Corporate debt securities    
Debt Securities, Available-for-sale [Line Items]    
Unrealized losses less than 12 months, fair value 431.2 44.5
Unrealized losses less than 12 months, gross unrealized losses (13.3) 0.0
Unrealized losses more than 12 months, fair value 14.8 73.6
Unrealized losses more than 12 months, gross unrealized losses (0.1) (0.7)
Total unrealized losses, fair value 446.0 118.1
Total unrealized losses, gross unrealized losses (13.4) (0.7)
U.S. government agencies    
Debt Securities, Available-for-sale [Line Items]    
Unrealized losses less than 12 months, fair value 124.7 0.0
Unrealized losses less than 12 months, gross unrealized losses (0.6) 0.0
Unrealized losses more than 12 months, fair value 0.0 29.2
Unrealized losses more than 12 months, gross unrealized losses 0.0 (0.1)
Total unrealized losses, fair value 124.7 29.2
Total unrealized losses, gross unrealized losses $ (0.6) $ (0.1)