Goodwill and Acquired Intangible Assets (Schedule of Changes in Goodwill) (Details) $ in Millions	9 Months Ended
Sep. 30, 2026 USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 14,371
Goodwill acquired	70
Foreign currency translation adjustments	(194)
Balance at end of period	14,247
Capital Access Platforms
Goodwill [Roll Forward]
Balance at beginning of period	4,285
Goodwill acquired	70
Foreign currency translation adjustments	(83)
Balance at end of period	4,272
Financial Technology
Goodwill [Roll Forward]
Balance at beginning of period	7,952
Foreign currency translation adjustments	(13)
Balance at end of period	7,939
Market Services
Goodwill [Roll Forward]
Balance at beginning of period	2,134
Foreign currency translation adjustments	(98)
Balance at end of period	$ 2,036

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