The amount of charges for unutilized infrastructures.

No definition available.

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Namespace Prefix:	E_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of revision of estimates related to decommissioning, restoration and rehabilitation.

+ References

No definition available.

+ Details

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Namespace Prefix:	E_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of provision for environmental risks.

+ References

No definition available.

+ Details

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

- Definition

The represents the amount of loss adjustments and actuarial provisions.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The represents the amount of provision for redundancy incentives.

+ References

No definition available.

+ Details

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

- Definition

The amount of provision for taxes.

+ References

No definition available.

+ Details

Name:	E_ProvisionForTaxes
Namespace Prefix:	E_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The receivable of amount from reinsurance.

+ References

No definition available.

+ Details

Name:	E_ReinsuranceContractsReceivable
Namespace Prefix:	E_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The discount rate used in the current estimate of the present value of the future cash flows expected to be derived from an asset or cash-generating unit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2017-01-01
-Paragraph 130
-Subparagraph g
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_130_g&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The increase (decrease) in other provisions resulting from a change in discount rate. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Paragraph 84
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_84_e&doctype=Standard
-URIDate 2017-03-09

+ Details

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

- Definition

The amount of provision for legal proceedings. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Section Example 10 A court case
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=sect_Example10Acourtcase&doctype=Illustrative%20Examples
-URIDate 2017-03-09

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-Paragraph 87
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_87&doctype=Standard
-URIDate 2017-03-09

+ Details

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

- Definition

The amount of provision for onerous contracts. An onerous contract is a contract in which the unavoidable costs of meeting the obligation under the contract exceed the economic benefits expected to be received under it. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Section Example 8 An onerous contract
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-02&anchor=sect_Example8Anonerouscontract&doctype=Illustrative%20Examples&book=B
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Paragraph 66
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_66&doctype=Standard
-URIDate 2017-03-09

+ Details

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

- Definition

The amount of provision for costs related to decommissioning, restoration and rehabilitation. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Section D Examples: disclosures
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=sect_DExamples:disclosures&doctype=Illustrative%20Examples
-URIDate 2017-03-09

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-Number 37
-IssueDate 2017-01-01
-Paragraph 87
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_87&doctype=Standard
-URIDate 2017-03-09

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfProvisionsAxis=E_ProvisionForRedundancyIncentivesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfProvisionsAxis=ifrs-full_OnerousContractsProvisionMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	ifrs-full_SegmentConsolidationItemsAxis=E_RefiningAndMarketingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Balance Type:
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- Details

Name:	ifrs-full_SegmentConsolidationItemsAxis=E_GasAndPowerSegmentMember
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Balance Type:
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- Details

Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=E_SyndialSpAMember
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Balance Type:
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- Details

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Data Type:	na
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- Details

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Data Type:	na
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- Details

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Provisions for contingencies (Details Textual) - EUR (€) € in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Provision for decommissioning, restoration and rehabilitation costs	€ 81	€ 118	€ 131
Increase (decrease) through change in discount rate, other provisions	264
Environment related provision	2,653
Legal proceedings provision	1,107
Provision for taxes	527
Charges for unutilized infrastructures	99
Loss adjustments and actuarial provisions [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Loss adjustments and actuarial provisions	205
Reinsurance contracts receivable	157
Provision for redundancy incentives [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Increase (decrease) through change in discount rate, other provisions	1
Provision for redundancy incentives	140
Onerous Contracts Provision [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Increase (decrease) through change in discount rate, other provisions	2
Onerous contracts provision	60
Refining & Marketing [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Environment related provision	326
Exploration & Production segment [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Legal proceedings provision	494
Provision for taxes	499
Gas & Power Segment [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Legal proceedings provision	457
Syndial SpA [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Environment related provision	€ 2,119
Bottom Of Range [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Discount rate used in current estimate of value in use	0.10%	(0.01%)
Top Of Range [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Discount rate used in current estimate of value in use	5.90%	5.80%
Exploration Production Segment [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Provision for decommissioning, restoration and rehabilitation costs	€ 7,649
Oil and natural gas [Member]
DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatoryLineItems [Line Items]
Provision for decommissioning, restoration and rehabilitation costs	8,126
Decommissioning costs, Revision of Previous Estimates	370
Increase (decrease) through change in discount rate, other provisions	€ 271