Intangible Assets Including Goodwill - Goodwill by Segment (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Changes in Goodwill Balances
Beginning Balance	$ 55,949	$ 55,643
Goodwill Additions	3,854	1,934
Purchase Price Adjustments	(1)	(159)
Divestitures	0	(485)
Foreign Currency Translation and Other Adjustments	(205)	(984)
Ending Balance	59,596	55,949
Goodwill impairment losses	0	0
Goodwill accumulated impairment losses	0	0
Software
Changes in Goodwill Balances
Beginning Balance	43,657	43,966
Goodwill Additions	3,447	568
Purchase Price Adjustments	(7)	(118)
Divestitures	0	0
Foreign Currency Translation and Other Adjustments	(173)	(760)
Ending Balance	46,923	43,657
Consulting
Changes in Goodwill Balances
Beginning Balance	7,928	6,797
Goodwill Additions	395	1,366
Purchase Price Adjustments	6	(42)
Divestitures	0	0
Foreign Currency Translation and Other Adjustments	(26)	(192)
Ending Balance	8,302	7,928
Infrastructure
Changes in Goodwill Balances
Beginning Balance	4,363	4,396
Goodwill Additions	12	0
Purchase Price Adjustments	0	0
Divestitures	0	(1)
Foreign Currency Translation and Other Adjustments	(5)	(32)
Ending Balance	4,370	4,363
Other
Changes in Goodwill Balances
Beginning Balance	0	484
Goodwill Additions	0	0
Purchase Price Adjustments	0	0
Divestitures	0	(484)
Foreign Currency Translation and Other Adjustments	0	0
Ending Balance	$ 0	$ 0

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