Goodwill and other intangible assets - Intangible assets - Narrative (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible asset amortization expense	$ 898	$ 863
Intangible assets with indefinite lives, excluding goodwill	$ 19,000		$ 18,900

Amount of amortization expense for finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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+ Details