Stock-Based Compensation - Stock-Based Compensation Cost (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 506	$ 401
Income tax benefits	(207)	(194)
Total net stock-based compensation cost	299	207
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	76	65
Selling, general and administrative
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	270	217
Research and development
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 160	$ 119

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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