Financial and derivative instruments - Summary of net notional long/(short) position of derivative instruments (Detail) - bbl bbl in Thousands	Mar. 31, 2021	Dec. 31, 2020
Crude barrels [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	220	(800)
Products barrels [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	(560)	(390)

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.

No definition available.

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