Note 18 - Intangible assets - Goodwill - Breakdown by CGU and Changes of the year - Business Combinations (Details)	12 Months Ended
Dec. 31, 2017
Intangible Assets and Goodwill Abstract
Description of nature and financial effect of business combinations during period	There were no significant business combinations.

The description of the nature and financial effect of business combinations during the current reporting period. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2016-01-13
-Paragraph 59
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2016-03-30&anchor=para_59_a&doctype=Standard
-URIDate 2016-03-31

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration