Investments (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Investments
Book amount - beginning of the year	€ 7,044	€ 3,511
Additions and subscriptions	2,992	120
Divestments and reimbursements	(22)	(151)
Share of profit of equity-accounted investments	161	409
Share of loss of equity-accounted investments	(184)	(430)
Deduction for dividends	(1,138)	(50)
Change in the scope of consolidation	1	3,448
Currency translation differences	86	81
Other changes	73	143
Book amount - end of the year	9,035	7,044
Investments in unconsolidated entities controlled by Eni
Investments
Book amount - beginning of the year	95	116
Additions and subscriptions	6
Divestments and reimbursements	(5)	(33)
Share of profit of equity-accounted investments	6	8
Share of loss of equity-accounted investments	(10)	(5)
Deduction for dividends	(4)	(6)
Change in the scope of consolidation	1
Currency translation differences	2	2
Other changes	(5)	13
Book amount - end of the year	86	95
Joint ventures
Investments
Book amount - beginning of the year	5,497	2,332
Additions and subscriptions	76	28
Divestments and reimbursements		(3)
Share of profit of equity-accounted investments	80	16
Share of loss of equity-accounted investments	(157)	(415)
Deduction for dividends	(1,073)	(19)
Change in the scope of consolidation		3,448
Currency translation differences	67	25
Other changes	80	119
Book amount - end of the year	4,592	5,497
Associates
Investments
Book amount - beginning of the year	1,452	1,063
Additions and subscriptions	2,910	92
Divestments and reimbursements	(17)	(115)
Share of profit of equity-accounted investments	75	385
Share of loss of equity-accounted investments	(17)	(10)
Deduction for dividends	(61)	(25)
Currency translation differences	17	54
Other changes	(2)	11
Book amount - end of the year	4,357	1,452
Changes in accounting policies (IFRS 9 and 15)
Investments
Book amount - beginning of the year		(37)
Changes in accounting policies (IFRS 9 and 15) \| Joint ventures
Investments
Book amount - beginning of the year		(34)
Changes in accounting policies (IFRS 9 and 15) \| Associates
Investments
Book amount - beginning of the year		(3)
Changes in accounting policies (IAS 28)
Investments
Book amount - beginning of the year	22
Book amount - end of the year		22
Changes in accounting policies (IAS 28) \| Joint ventures
Investments
Book amount - beginning of the year	22
Book amount - end of the year		22
After initial application
Investments
Book amount - beginning of the year	7,066	3,474
Book amount - end of the year		7,066
After initial application \| Investments in unconsolidated entities controlled by Eni
Investments
Book amount - beginning of the year	95	116
Book amount - end of the year		95
After initial application \| Joint ventures
Investments
Book amount - beginning of the year	5,519	2,298
Book amount - end of the year		5,519
After initial application \| Associates
Investments
Book amount - beginning of the year	€ 1,452	1,060
Book amount - end 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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name IFRS
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-IssueDate 2019-01-01
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-URIDate 2019-03-27

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