Accounting Policies and Supplemental Disclosures - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accounting Policies [Abstract]
Cash paid for interest on debt, net of capitalized interest	$ 465	$ 304	$ 1,821	$ 932	$ 2,450	$ 1,299
Cash paid for operating leases	2,692	1,813	7,687	6,268	10,052	7,961
Cash paid for interest on finance leases	76	88	234	290	318	404
Cash paid for interest on financing obligations	50	39	150	152	205	189
Cash paid for income taxes, net of refunds	2,628	742	6,982	4,340	8,677	4,674
Assets acquired under operating leases	3,345	6,755	11,075	14,031	15,844	19,839
Property and equipment acquired under finance leases, net of remeasurements and modifications	183	131	431	358	748	1,966
Property and equipment recognized during the construction period of build-to-suit lease arrangements	93	526	308	2,877	618	4,847
Property and equipment derecognized after the construction period of build-to-suit lease arrangements, with the associated leases recognized as operating	$ 492	$ 2,195	$ 1,212	$ 3,307	$ 3,063	$ 3,363