v3.26.3
Fair Value of Financial Information - Measurements of Assets and Liabilities on Recurring Basis (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Assets:    
Restricted funds $ 34 $ 41
Rabbi trust investments 36 32
Deposits 114 124
Mark-to-market derivative asset   2
Total assets 213 254
Liabilities:    
Deferred compensation obligations 40 38
Total liabilities 40 38
Total assets 173 216
Fixed-income securities    
Assets:    
Other investments   35
Money market and other    
Assets:    
Other investments 29 20
Level 1    
Assets:    
Restricted funds 34 41
Rabbi trust investments 36 32
Deposits 114 124
Mark-to-market derivative asset   0
Total assets 213 245
Liabilities:    
Deferred compensation obligations 40 38
Total liabilities 40 38
Total assets 173 207
Level 1 | Fixed-income securities    
Assets:    
Other investments   28
Level 1 | Money market and other    
Assets:    
Other investments 29 20
Level 2    
Assets:    
Restricted funds 0 0
Rabbi trust investments 0 0
Deposits 0 0
Mark-to-market derivative asset   2
Total assets 0 9
Liabilities:    
Deferred compensation obligations 0 0
Total liabilities 0 0
Total assets 0 9
Level 2 | Fixed-income securities    
Assets:    
Other investments   7
Level 2 | Money market and other    
Assets:    
Other investments 0 0
Level 3    
Assets:    
Restricted funds 0 0
Rabbi trust investments 0 0
Deposits 0 0
Mark-to-market derivative asset   0
Total assets 0 0
Liabilities:    
Deferred compensation obligations 0 0
Total liabilities 0 0
Total assets 0 0
Level 3 | Fixed-income securities    
Assets:    
Other investments   0
Level 3 | Money market and other    
Assets:    
Other investments $ 0 $ 0