Trade and other receivables - Net (impairment losses) reversals (Details) - Trade and other receivables - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Net (impairment losses) reversals of trade and other receivables
New or increased provisions	€ (620)	€ (498)
Credit losses	(45)	(37)
Reversals	233	120
Impairment loss on financial assets	€ (432)	€ (415)

Credit losses allowance recognised in profit or loss allowance account for credit losses of financial assets.

No definition available.

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

- Definition

The amount of additional allowance for credit losses of financial assets recognised in profit or loss. [Refer: Allowance account for credit losses of financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_AdditionalAllowanceRecognisedInProfitOrLossAllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

The amount of impairment loss on financial assets. [Refer: Financial assets; Impairment loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 20
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_20_e&doctype=Standard&book=b
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_ImpairmentLossOnFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The decrease in an allowance account for credit losses of financial assets resulting from the reversal of impairment. [Refer: Allowance account for credit losses of financial assets]

+ References

+ Details

Name:	ifrs-full_ReversalAllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	ifrs-full_ClassesOfAssetsAxis=e_TradeAndOtherCurrentReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: