Supplemental financial information - Treasury Stock (Details) - shares shares in Millions	3 Months Ended
Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning (in shares)			830
Balance, ending (in shares)	832
Treasury Common Stock
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning (in shares)	832	832	830
Repurchases (in shares)	1	1	4
Shares issued for stock compensation (in shares)	(1)	(1)	(2)
Balance, ending (in shares)	832	832	832

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Topic 505
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-Section S99
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-Publisher FASB
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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
-SubTopic 30
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481549/505-30-45-1

+ Details

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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
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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