Assets held for sale and divestitures - Narrative (Details) - Disposal group, held-for-sale, not discontinued operations - Lime operations - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Nov. 30, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration		$ 1,100
Gain (loss) on disposal	$ 115

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-3B

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483499/205-20-50-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483475/205-20-45-3

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Period Type:	duration