Discontinued operations - schedule of transaction proceeds and net assets disposed (Details) - Discontinued operations, disposed of by sale - Alliance Healthcare $ in Millions	Jun. 01, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Estimated fair value of proceeds from disposition	$ 6,900
Net assets disposed	5,800
Gain before currency translation adjustments	1,100
Currency translation loss released due to disposition	(800)
Net gain on disposal of discontinued operation	322
Base consideration	$ 6,275

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount of foreign currency translation gain (loss) in the disposal group, including discontinued operation, recognized in the statement of income as a result of the sale or complete or substantially complete liquidation of an investment in a foreign entity.

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