Changes in accounting policies (Details) $ in Millions	Dec. 31, 2021 USD ($)
Changes in accounting policies
Nominal amount of instruments affected by amendments for interest rate benchmark reform	$ 1,750

Nominal amount of instruments affected by amendments for interest rate benchmark reform

No definition available.

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Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant