Discontinued operations - Narrative (Details) - Discontinued Operations, Held-for-sale - Alliance Healthcare - USD ($) $ in Millions	Jun. 01, 2021	Jan. 06, 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration from disposal		$ 6,500
Cash received from disposal	$ 6,275	$ 6,275
Shares issued as part of disposal (in shares)	2,000,000	2,000,000

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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- Definition

Noncash or Part Noncash Divestiture, Noncash Consideration, Shares Issued

+ References

No definition available.

+ Details

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- Details

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