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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of liability recognized arising from contingent consideration in a business combination.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Business Acquisitions and Divestitures - Acquisitions (Details) - USD ($) $ in Millions	Nov. 01, 2022	Oct. 31, 2022	Dec. 31, 2022	Mar. 31, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill			$ 9,934	$ 9,451
U.S. Pharmaceutical
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill			$ 4,050	$ 3,923
McKesson and HCA Healthcare, Joint Oncology Research Business \| U.S. Pharmaceutical
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business acquisition, percentage of controlling interest in combined business		51.00%
Cash payment to acquire business		$ 173
Acquired identifiable intangible assets		$ 177
Weighted average life of intangibles		17 years
Goodwill		$ 120
Goodwill, expected tax deductible amount		49
Noncontrolling interest		225
McKesson and HCA Healthcare, Joint Oncology Research Business \| U.S. Pharmaceutical \| USOR
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling interest		20
McKesson and HCA Healthcare, Joint Oncology Research Business \| U.S. Pharmaceutical \| SCRI
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling interest		$ 205
Rx Savings Solutions, LLC \| RxTs Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business acquisition, percentage of controlling interest in combined business	100.00%
Cash payment to acquire business	$ 600
Contingent consideration	275
Other non-current liabilities	92
Acquired identifiable intangible assets	$ 229
Weighted average life of intangibles	12 years
Goodwill	$ 463