Goodwill and Acquired Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Indefinite-lived Intangible Assets [Line Items]
Goodwill, impairment loss	$ 0	$ 0	$ 0	$ 0
Finite-lived intangible assets, net	5,005,000,000		5,005,000,000		$ 5,272,000,000
Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	4,117,000,000		4,117,000,000		4,279,000,000
Foreign currency translation adjustment
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	(46,000,000)		(46,000,000)		$ (50,000,000)
Gain (loss) foreign currency translation adjustment			$ (46,000,000)
Customer Relationships And Licenses
Indefinite-lived Intangible Assets [Line Items]
Intangible asset, impairment loss	$ 20,000,000