Equity Activity - Reclassifications and Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	$ 6,820	$ 6,974	$ 13,539	$ 13,717
SG&A expense	4,938	4,900	9,912	9,754
Other (income) and expense	(233)	(261)	(550)	(506)
Interest expense	427	423	859	790
Services
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	5,126	5,294	10,365	10,604
Sales
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	1,607	1,587	2,988	2,910
Financing
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	86	93	186	203
Accumulated Other Comprehensive Income/(Loss)
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other Comprehensive Income (Loss), before Tax	322	381	885	289
Other comprehensive income/(loss), Tax (Expense)/Benefit	(153)	(101)	(442)	(48)
Other comprehensive income/(loss)	169	280	442	241
Unrealized gains/(losses) arising during the period, Net of Tax Amount			42	167
Reclassification/amortization, Net of Tax Amount			400	74
Accumulated Foreign Currency Adjustment Attributable to Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other Comprehensive Income (Loss), before Tax	2	116	57	29
Other comprehensive income/(loss), Tax (Expense)/Benefit	(68)	(34)	(222)	22
Other comprehensive income/(loss)	(66)	82	(165)	52
Unrealized gains/(losses) arising during the period, Net of Tax Amount			(165)	52
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other Comprehensive Income (Loss), before Tax	1	(17)	1	(1)
Other comprehensive income/(loss), Tax (Expense)/Benefit	0	4	0	0
Other comprehensive income/(loss)	0	(12)	1	(1)
Unrealized gains/(losses) arising during the period, Before Tax Amount	1	(17)	1	(1)
Unrealized gains/(losses) arising during the period, Tax (Expense)/Benefit	0	4	0	0
Unrealized gains/(losses) arising during the period, Net of Tax Amount	0	(12)	1	(1)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other Comprehensive Income (Loss), before Tax	61	148	307	(3)
Other comprehensive income/(loss), Tax (Expense)/Benefit	(16)	(40)	(79)	(1)
Other comprehensive income/(loss)	45	109	227	(4)
Unrealized gains/(losses) arising during the period, Before Tax Amount	103	178	279	149
Unrealized gains/(losses) arising during the period, Tax (Expense)/Benefit	(28)	(48)	(75)	(41)
Unrealized gains/(losses) arising during the period, Net of Tax Amount	75	130	204	107
Reclassification/amortization, Net of Tax Amount			24	(112)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Cost of services
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	3	(1)	4	(1)
Reclassification/amortization, Net of Tax Amount	(7)	2	(10)	4
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Cost of sales
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	5	1	9	5
Reclassification/amortization, Net of Tax Amount	(10)	(1)	(18)	(12)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Cost of financing
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	0	(1)	(1)	(2)
Reclassification/amortization, Net of Tax Amount	1	3	2	7
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | SG&A expense
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	2	0	3	3
Reclassification/amortization, Net of Tax Amount	(5)	0	(7)	(7)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Other (income) and expense
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	5	14	(15)	45
Reclassification/amortization, Net of Tax Amount	(16)	(41)	44	(135)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest expense
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Tax (Expense)/Benefit	(2)	(5)	(4)	(11)
Reclassification/amortization, Net of Tax Amount	6	16	13	32
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Reclassification out of Accumulated Other Comprehensive Income
Reclassifications and Taxes Related to Items of Other Comprehensive Income
SG&A expense	(7)	(1)	(10)	(10)
Other (income) and expense	(21)	(55)	58	(181)
Interest expense	8	22	17	42
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Reclassification out of Accumulated Other Comprehensive Income | Services
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	(9)	3	(14)	5
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Reclassification out of Accumulated Other Comprehensive Income | Sales
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	(15)	(2)	(27)	(17)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Reclassification out of Accumulated Other Comprehensive Income | Financing
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Cost	2	4	3	9
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Other Comprehensive Income (Loss), before Tax	259	134	520	263
Other comprehensive income/(loss), Tax (Expense)/Benefit	(69)	(31)	(141)	(69)
Other comprehensive income/(loss)	190	102	379	194
Unrealized gains/(losses) arising during the period, Net of Tax Amount			2	9
Reclassification/amortization, Net of Tax Amount			377	185
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Unrealized gains/(losses) arising during the period, Before Tax Amount	0	0	0	0
Unrealized gains/(losses) arising during the period, Tax (Expense)/Benefit	0	0	0	1
Unrealized gains/(losses) arising during the period, Net of Tax Amount	0	0	0	1
Reclassification/amortization, Before Tax Amount	(2)	(2)	(4)	(4)
Reclassification/amortization, Tax (Expense)/Benefit	0	1	1	1
Reclassification/amortization, Net of Tax Amount	(1)	(2)	(3)	(3)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Unrealized gains/(losses) arising during the period, Before Tax Amount	0	0	1	2
Unrealized gains/(losses) arising during the period, Tax (Expense)/Benefit	2	7	2	7
Unrealized gains/(losses) arising during the period, Net of Tax Amount	2	7	2	8
Reclassification/amortization, Before Tax Amount	258	130	519	261
Reclassification/amortization, Tax (Expense)/Benefit	(71)	(38)	(143)	(76)
Reclassification/amortization, Net of Tax Amount	187	92	376	185
Retirement-Related Benefit Plans, Curtailments and Settlements
Reclassifications and Taxes Related to Items of Other Comprehensive Income
Reclassification/amortization, Before Tax Amount	2	6	4	5
Reclassification/amortization, Tax (Expense)/Benefit	(1)	(1)	(1)	(1)
Reclassification/amortization, Net of Tax Amount	$ 2	$ 5	$ 3	$ 4