v3.25.2
Valuation of debt and equity investments and certain liabilities - Fair Value Assets and Liabilities Measured on Recurring Basis (Details) - Recurring - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value $ 4,993 $ 6,848
Total liabilities fair value 445 443
Deferred compensation    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total liabilities fair value 445 443
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 2,823 3,364
Total liabilities fair value 445 443
Level 1 | Deferred compensation    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total liabilities fair value 445 443
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 2,170 3,484
Total liabilities fair value 0 0
Level 2 | Deferred compensation    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total liabilities fair value 0 0
Money market funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 682 762
Money market funds | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 682 762
Money market funds | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 0 0
Corporate obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 1,125 1,490
Corporate obligations | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 0 0
Corporate obligations | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 1,125 1,490
U.S. government and agency securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 2,927 4,237
U.S. government and agency securities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 2,130 2,591
U.S. government and agency securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 797 1,646
Non-U.S. government and agency securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 248 348
Non-U.S. government and agency securities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 0 0
Non-U.S. government and agency securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 248 348
Mutual funds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 11 11
Mutual funds | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value 11 11
Mutual funds | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets fair value $ 0 $ 0