Redeemable noncontrolling interests (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Equity, Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	$ 430	$ 384
Adjustment to the redemption value	7	7
Dividends paid	(15)	(12)
Ending balance	$ 422	$ 379

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479887/480-10-S45-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479857/480-10-S50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479887/480-10-S45-3

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3A
-Subparagraph (24)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480244/480-10-S99-3A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (01)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480244/480-10-S99-1

Name:	us-gaap_RedeemableNoncontrollingInterestEquityCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant