Investments (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Investments
Book amount - beginning of the year	€ 9,035	€ 7,044
Additions and subscriptions	275	2,992
Divestments and reimbursements	(4)	(22)
Share of profit of equity-accounted investments	38	161
Share of loss of equity-accounted investments	(1,733)	(184)
Deduction for dividends	(314)	(1,138)
Change in the scope of consolidation	34	1
Currency translation differences	(603)	86
Other changes	21	73
Book amount - end of the year	6,749	9,035
Investments in unconsolidated entities controlled by Eni
Investments
Book amount - beginning of the year	86	95
Additions and subscriptions	2	6
Divestments and reimbursements		(5)
Share of profit of equity-accounted investments	3	6
Share of loss of equity-accounted investments	(2)	(10)
Deduction for dividends	(5)	(4)
Change in the scope of consolidation	3	1
Currency translation differences	(4)	2
Other changes	(3)	(5)
Book amount - end of the year	80	86
Joint ventures
Investments
Book amount - beginning of the year	4,592	5,497
Additions and subscriptions	75	76
Divestments and reimbursements	(3)
Share of profit of equity-accounted investments	21	80
Share of loss of equity-accounted investments	(1,399)	(157)
Deduction for dividends	(296)	(1,073)
Change in the scope of consolidation	30
Currency translation differences	(254)	67
Other changes	66	80
Book amount - end of the year	2,832	4,592
Associates
Investments
Book amount - beginning of the year	4,357	1,452
Additions and subscriptions	198	2,910
Divestments and reimbursements	(1)	(17)
Share of profit of equity-accounted investments	14	75
Share of loss of equity-accounted investments	(332)	(17)
Deduction for dividends	(13)	(61)
Change in the scope of consolidation	1
Currency translation differences	(345)	17
Other changes	(42)	(2)
Book amount - end of the year	€ 3,837	4,357
Changes in accounting policies (IAS 28)
Investments
Book amount - beginning of the year		22
Changes in accounting policies (IAS 28) \| Joint ventures
Investments
Book amount - beginning of the year		22
After initial application
Investments
Book amount - beginning of the year		7,066
After initial application \| Investments in unconsolidated entities controlled by Eni
Investments
Book amount - beginning of the year		95
After initial application \| Joint ventures
Investments
Book amount - beginning of the year		5,519
After initial application \| Associates
Investments
Book amount - beginning of the year		€ 1,452

The amount of additions and subscriptions to investments accounted for using equity method.

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It represents the changes in scope of consolidation.

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No definition available.

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It represents the deduction for dividends.

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Disclosure Of Investments

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The amount of divestments and reimbursements of investments accounted for using equity method.

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No definition available.

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The increase (decrease) in investments using equity method resulting from changes that the entity does not separately disclose in the same statement or note.

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No definition available.

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The increase (decrease) through net exchange differences investments using equity method.

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It represents the share of loss of equity accounted investments.

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It represents the share of profit of equity accounted investments.

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The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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