Derivative financial instruments (Details) € in Millions	Dec. 31, 2018 EUR (€) bbl	Dec. 31, 2017 EUR (€) bbl
Disclosure Of Derivative Financial Instruments [Line Items]
Fair value of derivative financial instruments	€ 1,594	€ 1,231
- non-current	68	80
Fair value of derivatives financial instruments	1,445	1,011
- non-current	40	91
Non Hedging Derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	1,501	1,101
Derivative financial liabilities	€ 1,524	€ 1,011
Non Hedging Derivatives [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Level of fair value \| bbl	2	2
Non Hedging Derivatives [Member] \| Level 1 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Level of fair value \| bbl	1	1
Non Hedging Derivatives [Member] \| Futures contract [Member] \| Level 1 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 1,060	€ 796
Derivative financial liabilities	1,107	771
Non Hedging Derivatives [Member] \| Over the Counter Contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	306	81
Derivative financial liabilities	284	97
Non Hedging Derivatives [Member] \| Other Contracts [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 1	€ 1
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 5	€ 2
Cash flow hedge derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 337	€ 262
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 211	€ 21
Cash flow hedge derivatives [Member] \| Futures contract [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Level of fair value \| bbl	1	1
Cash flow hedge derivatives [Member] \| Futures contract [Member] \| Level 1 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 26	€ 35
Derivative financial liabilities	€ 15
Cash flow hedge derivatives [Member] \| Over the Counter Contract [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Level of fair value \| bbl	2	2
Cash flow hedge derivatives [Member] \| Over the Counter Contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 311	€ 227
Derivative financial liabilities	196	21
Trading Derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	1,439	1,211
Derivative financial liabilities	1,365	1,333
Trading Derivatives [Member] \| Futures contract [Member] \| Level 1 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 367	€ 395
Level of fair value \| bbl	1	1
Derivative financial liabilities	€ 263	€ 390
Trading Derivatives [Member] \| Over the Counter Contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 992	€ 683
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 1,031	€ 829
Trading Derivatives [Member] \| Option contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 80	€ 133
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 71	€ 114
Option Embedded in Convertible Bonds [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	3,298	2,590
Offsetting	(1,636)	(1,279)
Net amount	1,662	1,311
Fair value of derivative financial instruments	1,594	1,231
- non-current	68	80
Derivative financial liabilities	3,121	2,381
Offsetting	(1,636)	(1,279)
Net amount	1,485	1,102
Fair value of derivatives financial instruments	1,445	1,011
- non-current	40	91
Option Embedded in Convertible Bonds [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	21	16
Derivative financial liabilities	21	16
Currency risk [Member] \| Non Hedging Derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	116	214
Derivative financial liabilities	122	136
Currency risk [Member] \| Non Hedging Derivatives [Member] \| Currency swap contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 99	€ 170
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 46	€ 86
Currency risk [Member] \| Non Hedging Derivatives [Member] \| Interest rate swap contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 14	€ 41
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 71	€ 45
Currency risk [Member] \| Non Hedging Derivatives [Member] \| Outright [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 3	€ 3
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 5	€ 5
Interest Rate Risk [Member] \| Non Hedging Derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	18	9
Derivative financial liabilities	6	5
Interest Rate Risk [Member] \| Non Hedging Derivatives [Member] \| Interest rate swap contract [Member] \| Level 2 of fair value hierarchy [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	€ 18	€ 9
Level of fair value \| bbl	2	2
Derivative financial liabilities	€ 6	€ 5
Commodity price risk [Member] \| Non Hedging Derivatives [Member]
Disclosure Of Derivative Financial Instruments [Line Items]
Derivative financial assets	1,367	878
Derivative financial liabilities	€ 1,396	€ 870

It represents the amount of derivative financial assets, net amount.

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It represents the amount of derivative financial liabilities, net amount.

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Disclosure of derivative financial instruments

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The element represents about the level of fair value.

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It represents the amount of offsetting of derivative financial assets.

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No definition available.

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It represents the amount of offsetting of derivative financial liabilities.

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No definition available.

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- Definition

The amount of current derivative financial assets. [Refer: Derivative financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2018-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_55&doctype=Standard
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The amount of current derivative financial liabilities. [Refer: Derivative financial liabilities]

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The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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The amount of non-current derivative financial assets. [Refer: Derivative financial assets]

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The amount of non-current derivative financial liabilities. [Refer: Derivative financial liabilities]

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