Finance debts - Convertible bonds (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Borrowings
Borrowings	€ 27,794	€ 26,686
Convertible Bonds
Borrowings
Borrowings	399	€ 396
ENI SpA \| Convertible Bonds
Borrowings
Nominal value	400
Discount on bond issue and accrued expenses	(1)
Borrowings	€ 399
Borrowings, original currency	EUR
Borrowings, maturity	2022
Borrowings, interest rate	0.00%

Disclosure Of Borrowings Explanatory

No definition available.

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- Definition

The amount of discount on bond issue and accrued expenses.

+ References

No definition available.

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- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The maturity of borrowings. [Refer: Borrowings]

+ References

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- Definition

The currency in which the borrowings are denominated. [Refer: Borrowings]

+ References

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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2021-01-01
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