Acquisitions and other investments - Schedule of Purchase Price Allocation and Identifiable Assets Acquired and Liabilities Assumed - CareCentrix (Details) - USD ($) $ in Millions	Aug. 31, 2022	May 31, 2023
Identifiable assets acquired and liabilities assumed:
Goodwill	$ 22,280	$ 28,371
CareCentrix, Inc
Purchase Price Allocation:
Cash consideration	327
Contingent consideration	4
Fair value of equity consideration	66
Fair value of non-controlling interests	217
Total	614
Identifiable assets acquired and liabilities assumed:
Tangible assets	358
Intangible assets	426
Liabilities	(680)
Total identifiable net assets	104
Goodwill	$ 509