Other comprehensive income - Items not reclassified: benefit plans (Details) - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Items not reclassified to profit or loss
Decrease in benefit liability from remeasurement	€ 833
Inflation rates	7.72%
SPAIN
Items not reclassified to profit or loss
Discount rates	1.10%	1.55%
UK
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ 314
Inflation rates	7.72%
BRAZIL \| Pension defined benefit plans [member]
Items not reclassified to profit or loss
Discount rates	7.72%	9.11%
BRAZIL \| Post-employment medical defined benefit plans [member]
Items not reclassified to profit or loss
Discount rates	7.86%	9.26%
United Kingdom and Brazil
Items not reclassified to profit or loss
Discount rates	2.35%	2.90%
Discount rate actuarial assumptions \| SPAIN
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ 161
Discount rate actuarial assumptions \| BRAZIL
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	304
Discount rate actuarial assumptions \| Other Regions [Member]
Items not reclassified to profit or loss
Increase (decrease) in accumulated actuarial losses/profits	€ 54

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 144
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_144&doctype=Standard
-URIDate 2018-03-16

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- Definition

The expected rate of inflation that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]]

+ References

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 141
-Subparagraph c
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c_iii&doctype=Standard
-URIDate 2018-03-16

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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No definition available.

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c&doctype=Standard
-URIDate 2018-03-16

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