Segment Information - Revenue to EBITDA (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Revenue from External Customer [Line Items]
Revenues	$ 2,899	$ 3,182
Operating expenses
Cost of services and products related to network expenses	1,435	1,687
Net gain on sale of business	(596)	0
Reportable Segment
Revenue from External Customer [Line Items]
Revenues	2,899	3,182
Operating expenses
Cost of services and products related to network expenses	837	1,018
Headcount costs	643	619
Non-headcount costs	736	715
Net gain on sale of business	(596)	0
Adjusted EBITDA	$ 1,279	$ 830

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details