v3.26.1
Fair Value of Financial Instruments (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Input Level 2 | Carrying Amount    
Fair Value Disclosure    
Long-term debt (excluding finance leases) $ 1,686 $ 1,686
Input Level 2 | Fair Value    
Fair Value Disclosure    
Long-term debt (excluding finance leases) 1,281 1,261
Input Level 3 | Carrying Amount    
Fair Value Disclosure    
Regulatory cost liability related to the sale of the Mass Markets Fiber-to-the-Home business 18 0
Input Level 3 | Fair Value    
Fair Value Disclosure    
Regulatory cost liability related to the sale of the Mass Markets Fiber-to-the-Home business $ 18 $ 0