Intangible Assets Including Goodwill - Goodwill by Segment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Changes in Goodwill Balances
Beginning Balance	$ 55,643	$ 53,765
Goodwill Additions	649	2,549
Purchase Price Adjustments	(31)	2
Divestitures	(1)	(50)
Foreign Currency Translation and Other Adjustments	(153)	(623)
Ending Balance	56,106	55,643
Goodwill impairment losses	0	0
Goodwill accumulated impairment losses	0	0
Business Segments \| Software
Changes in Goodwill Balances
Beginning Balance	43,966	42,665
Goodwill Additions	188	1,836
Purchase Price Adjustments	(27)	23
Divestitures		(13)
Foreign Currency Translation and Other Adjustments	(99)	(545)
Ending Balance	44,027	43,966
Business Segments \| Consulting
Changes in Goodwill Balances
Beginning Balance	6,797	6,145
Goodwill Additions	461	713
Purchase Price Adjustments	(3)	(21)
Foreign Currency Translation and Other Adjustments	(49)	(40)
Ending Balance	7,205	6,797
Business Segments \| Infrastructure
Changes in Goodwill Balances
Beginning Balance	4,396	4,436
Purchase Price Adjustments		0
Divestitures	(1)
Foreign Currency Translation and Other Adjustments	(5)	(39)
Ending Balance	4,390	4,396
Business Segments \| Other.
Changes in Goodwill Balances
Beginning Balance	484	520
Divestitures		(37)
Foreign Currency Translation and Other Adjustments		1
Ending Balance	$ 484	$ 484

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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