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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

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Financial and derivative instruments - Summary of net notional long/(short) position of derivative instruments (Detail) - bbl bbl in Thousands	Sep. 30, 2026	Dec. 31, 2025
Crude Oil \| Short
Derivative [Line Items]
Derivative, nonmonetary notional amount, volume	4,234
Crude Oil \| Long
Derivative [Line Items]
Derivative, nonmonetary notional amount, volume		954
Products \| Short
Derivative [Line Items]
Derivative, nonmonetary notional amount, volume		702
Products \| Long
Derivative [Line Items]
Derivative, nonmonetary notional amount, volume	376