v3.26.3
Segment Information - Revenue to EBITDA (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues $ 2,715 $ 3,087 $ 8,419 $ 9,361
Operating expenses        
Cost of services and products related to network expenses 1,432 1,700 4,282 5,011
Net gain on sale of business (4) 0 (569) 0
Reportable Segment        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 2,715 3,087 8,419 9,361
Operating expenses        
Cost of services and products related to network expenses 800 929 2,450 2,846
Headcount costs 617 685 1,851 1,953
Non-headcount costs 781 902 2,289 2,436
Net gain on sale of business (4) 0 (569) 0
Adjusted EBITDA $ 521 $ 571 $ 2,398 $ 2,126