Segment Information - Reportable Segments and Reconciliation to Consolidated Net Income (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2025 USD ($) segment	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	3
Segment Reporting Disclosure [Line Items]
Net sales	$ 155,667	$ 143,313
Operating expenses	137,262	128,006
Operating income	18,405	15,307
Total non-operating income (expense)	3,274	(2,324)
Provision for income taxes	(4,553)	(2,467)
Equity-method investment activity, net of tax	1	(85)
Net income	17,127	10,431	$ 65,944	$ 37,684
North America
Segment Reporting Disclosure [Line Items]
Net sales	92,887	86,341
Operating expenses	87,046	81,358
Operating income	5,841	4,983
International
Segment Reporting Disclosure [Line Items]
Net sales	33,513	31,935
Operating expenses	32,496	31,032
Operating income	1,017	903
AWS
Segment Reporting Disclosure [Line Items]
Net sales	29,267	25,037
Operating expenses	17,720	15,616
Operating income	$ 11,547	$ 9,421