Supplemental financial information - Treasury Stock (Details) - shares shares in Millions	3 Months Ended
Jun. 30, 2024	Mar. 31, 2024
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning (in shares)		832
Balance, ending (in shares)	828
Treasury Common Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning (in shares)	831	832
Repurchases (in shares)	0	0
Shares issued for stock compensation (in shares)	(3)	(1)
Balance, ending (in shares)	828	831

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

+ References

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-Name Accounting Standards Codification
-Section 50
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-SubTopic 10
-Topic 505
-Publisher FASB
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-Topic 210
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- Definition

Number of previously issued common shares repurchased by the issuing entity and held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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