v3.25.2
Fair Value (Carrying amount and estimated fair value of financial instrument assets and liabilities which are not measured at fair value) (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Assets    
Mortgage loans $ 1,040 $ 1,019
Liabilities    
Long-term debt 2,475 2,973
Carrying Amount    
Assets    
Mortgage loans 1,040 1,019
Liabilities    
Short-term debt 500 0
Long-term debt 2,475 2,973
Estimated Fair Value    
Assets    
Mortgage loans 1,026 987
Liabilities    
Short-term debt 499 0
Long-term debt 2,435 2,885
Level 1 | Estimated Fair Value    
Assets    
Mortgage loans 0 0
Liabilities    
Short-term debt 0 0
Long-term debt 0 0
Level 2 | Estimated Fair Value    
Assets    
Mortgage loans 0 0
Liabilities    
Short-term debt 499 0
Long-term debt 2,435 2,885
Level 3 | Estimated Fair Value    
Assets    
Mortgage loans 1,026 987
Liabilities    
Short-term debt 0 0
Long-term debt $ 0 $ 0