Goodwill and Purchased Intangible Assets - Goodwill by Segments (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,958
Additions	0
Other	(1)
Goodwill, ending balance	1,957
Network
Goodwill [Roll Forward]
Goodwill, beginning balance	1,702
Additions	0
Other	(1)
Goodwill, ending balance	1,701
Self-Service Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	256
Additions	0
Other	0
Goodwill, ending balance	256
Goodwill, accumulated impairment loss	$ 16	$ 16

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details