Goodwill and Other Intangible Assets - Schedule of Goodwill Rollforward (Details) $ in Millions	6 Months Ended
Jun. 30, 2026 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 30,646
Foreign currency translation	(14)
Goodwill, ending balance	30,632
Exchanges Segment
Goodwill [Roll Forward]
Goodwill, beginning balance	8,175
Foreign currency translation	(12)
Goodwill, ending balance	8,163
Fixed Income and Data Services Segment
Goodwill [Roll Forward]
Goodwill, beginning balance	4,864
Foreign currency translation	(1)
Goodwill, ending balance	4,863
Mortgage Technology Segment
Goodwill [Roll Forward]
Goodwill, beginning balance	17,607
Foreign currency translation	(1)
Goodwill, ending balance	$ 17,606

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