Guarantees, commitments and risks - Other information about financial instruments (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Guarantees, commitments and risks
Financial assets at fair value through profit or loss	€ 6,782	€ 8,251
Non-hedging and trading derivatives	837	2,006
Other investments valued at fair value	1,256	1,202	€ 1,294
Trade receivables and other	17,054	21,396
Financing receivables	3,163	3,415
Securities	61	56
Trade payables and other	20,808	25,897
Financing payables	28,729	26,917
Net assets (liabilities) for hedging derivatives	(35)	(129)
Financial assets at fair value through profit or loss, Income (expense) recognized in profit and loss account	284	(55)	€ 11
Non-hedging and trading derivatives, Income (expense) recognized in profit and loss account	417	(1,723)
Other investments valued at fair value, Income (expense) recognized in profit and loss account	255	351
Other investments valued at fair value, Income (expense) recognized in other comprehensive income	45	56
Trade receivables and other, Income (expense) recognized in profit and loss account	(285)	31
Financing receivables, Income (expense) recognized in profit and loss account	141	(16)
Securities, Income (expense) recognized in profit and loss account	1
Trade payables and other, Income (expense) recognized in profit and loss account	69	53
Financing payables, Income (expense) recognized in profit and loss account	(734)	(692)
Net assets (liabilities) for hedging derivatives, Income (expense) recognized in profit and loss account	(442)	(4,677)
Net assets (liabilities) for hedging derivatives, Income (expense) recognized in other comprehensive income	541	794
Other operating income (loss)
Guarantees, commitments and risks
Non-hedging and trading derivatives, Income (expense) recognized in profit and loss account	478	(1,736)
Financial income (expense)
Guarantees, commitments and risks
Non-hedging and trading derivatives, Income (expense) recognized in profit and loss account	(61)	13
Trade receivables and other, Income (expense) recognized in profit and loss account	36	16
Financing receivables, Income (expense) recognized in profit and loss account	144	86
Interest income calculated on the basis of the effective interest rate
Guarantees, commitments and risks
Trade receivables and other, Income (expense) recognized in profit and loss account	15	15
Interest expense calculated on the basis of the effective interest rate
Guarantees, commitments and risks
Financing receivables, Income (expense) recognized in profit and loss account	743	568
Net (impairment losses) reversal of trade and other receivables
Guarantees, commitments and risks
Trade receivables and other, Income (expense) recognized in profit and loss account	249	47
Net revaluations or impairments
Guarantees, commitments and risks
Financing receivables, Income (expense) recognized in profit and loss account	€ 6	€ 111

The amount of assets (liabilities) for hedging derivatives.

No definition available.

Name:	e_AssetsLiabilitiesForHedgingDerivatives
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of income (expense) recognized in profit and loss account of financing payables.

+ References

No definition available.

+ Details

Name:	e_FinancingPayablesFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of financing receivables.

+ References

No definition available.

+ Details

Name:	e_FinancingReceivables
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of income (expense) recognized in profit and loss account of trade receivables and other.

+ References

No definition available.

+ Details

Name:	e_FinancingReceivablesFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in other comprehensive income of hedging derivatives.

+ References

No definition available.

+ Details

Name:	e_HedgingDerivativesFinanceIncomeExpenseRecognizedInOtherComprehensiveIncome
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in profit and loss account of hedging derivatives.

+ References

No definition available.

+ Details

Name:	e_HedgingDerivativesFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of non-hedging and trading derivatives.

+ References

No definition available.

+ Details

Name:	e_NonHedgingAndTradingDerivatives
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of income (expense) recognized in profit and loss account of non-hedging and trading derivatives.

+ References

No definition available.

+ Details

Name:	e_NonHedgingAndTradingDerivativesFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in other comprehensive income of other investments valued at fair value.

+ References

No definition available.

+ Details

Name:	e_OtherInvestmentsValuedAtFairValueFinanceIncomeExpenseRecognizedInOtherComprehensiveIncome
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in profit and loss account of other investments valued at fair value.

+ References

No definition available.

+ Details

Name:	e_OtherInvestmentsValuedAtFairValueFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) derived from securities, which are recognized in profit and loss account.

+ References

No definition available.

+ Details

Name:	e_SecuritiesFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in profit and loss account of securities.

+ References

No definition available.

+ Details

Name:	e_TradePayablesAndOtherFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of income (expense) recognized in profit and loss account of trade receivables and other.

+ References

No definition available.

+ Details

Name:	e_TradeReceivablesAndOtherFinanceIncomeExpenseRecognizedInProfitAndLoss
Namespace Prefix:	e_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_55&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_Borrowings
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 8
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_8_a&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_CurrentFinancialAssetsAtFairValueThroughProfitOrLoss
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of instruments representing indebtedness held by the entity.

+ References

+ Details

Name:	ifrs-full_DebtInstrumentsHeld
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfContingentLiabilitiesLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 20
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20_a_i&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainsLossesOnFinancialAssetsAtFairValueThroughProfitOrLoss
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of non-current investments other than investments accounted for using the equity method. [Refer: Investments accounted for using equity method; Non-current assets; Investments other than investments accounted for using equity method]

+ References

+ Details

Name:	ifrs-full_NoncurrentInvestmentsOtherThanInvestmentsAccountedForUsingEquityMethod
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of trade payables and other payables. [Refer: Trade payables; Other payables]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 54
-Subparagraph k
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_k&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_TradeAndOtherPayables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of trade receivables and other receivables. [Refer: Trade receivables; Other receivables]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 54
-Subparagraph h
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_h&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 78
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_78_b&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_TradeAndOtherReceivables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	e_IncomeStatementAxis=e_OtherOperatingIncomeLossMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	e_IncomeStatementAxis=e_FinancialIncomeExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	e_IncomeStatementAxis=e_InterestIncomeCalculatedOnBasisOfEffectiveInterestRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	e_IncomeStatementAxis=e_InterestExpenseCalculatedOnBasisOfEffectiveInterestRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	e_IncomeStatementAxis=e_NetImpairmentLossesReversalOfTradeAndOtherReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	e_IncomeStatementAxis=e_NetRevaluationsOrImpairmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: