Intangible Assets Including Goodwill - Goodwill by Segment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Changes in Goodwill Balances
Beginning Balance	$ 60,178	$ 55,949
Goodwill Additions	195	3,953
Purchase Price Adjustments	(4)	(15)
Divestitures	(464)	0
Foreign Currency Translation and Other Adjustments	(372)	291
Ending Balance	59,534	60,178
Goodwill impairment losses	0	0
Goodwill accumulated impairment losses	0	0
Software
Changes in Goodwill Balances
Beginning Balance	46,447	42,712
Goodwill Additions	91	3,538
Purchase Price Adjustments	(4)	(17)
Divestitures	0	0
Foreign Currency Translation and Other Adjustments	(304)	214
Ending Balance	46,230	46,447
Consulting
Changes in Goodwill Balances
Beginning Balance	8,883	8,409
Goodwill Additions	96	403
Purchase Price Adjustments	0	2
Divestitures	0	0
Foreign Currency Translation and Other Adjustments	(57)	69
Ending Balance	8,922	8,883
Infrastructure
Changes in Goodwill Balances
Beginning Balance	4,384	4,363
Goodwill Additions	8	12
Purchase Price Adjustments	0	0
Divestitures	0	0
Foreign Currency Translation and Other Adjustments	(11)	8
Ending Balance	4,381	4,384
Other
Changes in Goodwill Balances
Beginning Balance	464	464
Goodwill Additions	0	0
Purchase Price Adjustments	0	0
Divestitures	(464)	0
Foreign Currency Translation and Other Adjustments	0	0
Ending Balance	$ 0	$ 464

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