Assets held for sale and liabilities directly associated with assets held for sale (Details Textual) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Discontinued Operations Explanatory [Line Items]
Proportion of ownership interest in subsidiary	80.00%
Liabilities included in disposal groups classified as held for sale	€ 59	€ 87
Tigaz Zrt [Member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Percentage of Ownership Interest Divested	98.99%
Tigaz dso [Member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Proportion of ownership interest in subsidiary	(100.00%)
Current Assets Or Disposal Group Classified As Held For Sale	€ 81
Current Lliabilities Included In Disposal Groups Classified As Held For Sale	33
Tigaz dso [Member] \| Gross carrying amount [member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Non-current assets or disposal groups classified as held for sale	274
Liabilities included in disposal groups classified as held for sale	59
Met holding [Member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Non-current assets or disposal groups classified as held for sale	295
Liabilities included in disposal groups classified as held for sale	€ 59
Lasmo sanga sanga [Member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Proportion of ownership interest in subsidiary	26.25%
Unimar Llc [Member]
Disclosure Of Discontinued Operations Explanatory [Line Items]
Proportion of ownership interest in subsidiary	50.00%
Non-current assets or disposal groups classified as held for sale	€ 21

The amount of current assets or disposal group classified as held for sale.

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The amount of current lliabilities included in disposal groups classified as held for sale.

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Disclosure Of Discontinued Operations Explanatory

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The percentage of ownership interest divested.

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No definition available.

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The amount of liabilities included in disposal groups classified as held for sale. [Refer: Liabilities; Disposal groups classified as held for sale [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of non-current assets or disposal groups classified as held for sale. [Refer: Disposal groups classified as held for sale [member]]

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The proportion of ownership interest in a subsidiary attributable to the entity. [Refer: Subsidiaries [member]]

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