Goodwill and other intangible assets - Intangible assets - Narrative (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible asset amortization expense	$ 863	$ 892
Intangible assets with indefinite lives, excluding goodwill	$ 18,900		$ 18,900

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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