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Acquisitions & Divestitures - Purchase Price Allocation (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Acquisitions
Goodwill	$ 59,596	$ 55,949	$ 55,643
2023 Acquisitions \| Client relationships \| Minimum
Acquisitions
Weighted average useful life	6 years
2023 Acquisitions \| Client relationships \| Maximum
Acquisitions
Weighted average useful life	10 years
2023 Acquisitions \| Completed technology \| Minimum
Acquisitions
Weighted average useful life	5 years
2023 Acquisitions \| Completed technology \| Maximum
Acquisitions
Weighted average useful life	7 years
2023 Acquisitions \| Trademarks \| Minimum
Acquisitions
Weighted average useful life	2 years
2023 Acquisitions \| Trademarks \| Maximum
Acquisitions
Weighted average useful life	5 years
Apptio
Acquisitions
Current assets	$ 150
Property, plant and equipment/noncurrent assets	35
Goodwill	3,552
Total assets acquired	5,042
Current liabilities	255
Noncurrent liabilities	177
Total liabilities assumed	432
Total purchase price	$ 4,610
Weighted average useful life	8 years 7 months 6 days
Apptio \| Client relationships
Acquisitions
Intangible assets	$ 740
Apptio \| Completed technology
Acquisitions
Intangible assets	530
Apptio \| Trademarks
Acquisitions
Intangible assets	35
Other 2023 Acquisitions
Acquisitions
Current assets	46
Property, plant and equipment/noncurrent assets	7
Goodwill	301
Total assets acquired	458
Current liabilities	26
Noncurrent liabilities	10
Total liabilities assumed	36
Total purchase price	$ 423
Weighted average useful life	6 years 8 months 12 days
Other 2023 Acquisitions \| Client relationships
Acquisitions
Intangible assets	$ 37
Other 2023 Acquisitions \| Completed technology
Acquisitions
Intangible assets	66
Other 2023 Acquisitions \| Trademarks
Acquisitions
Intangible assets	$ 2