The aggregate of property, plant and equipment and other noncurrent assets recognized as of the acquisition date.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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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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Acquisitions & Divestitures - Purchase Price Allocation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Acquisitions
Goodwill	$ 59,534	$ 60,178	$ 55,949
2024 Acquisitions
Acquisitions
Current assets	17
Property, plant and equipment/noncurrent assets	2
Goodwill	195
Total assets acquired	284
Current liabilities	13
Noncurrent liabilities	15
Total liabilities assumed	29
Total purchase price	255
2024 Acquisitions \| Client relationships
Acquisitions
Intangible assets	$ 31
2024 Acquisitions \| Client relationships \| Minimum
Acquisitions
Weighted average useful life	2 years
2024 Acquisitions \| Client relationships \| Maximum
Acquisitions
Weighted average useful life	7 years
2024 Acquisitions \| Completed technology
Acquisitions
Intangible assets	$ 37
Weighted average useful life	7 years
2024 Acquisitions \| Trademarks
Acquisitions
Intangible assets	$ 0
Weighted average useful life	3 years