Equity (Details 1) (Detail) shares in Thousands, pure in Thousands	12 Months Ended
Dec. 31, 2018 shares
Changes in equity [abstract]
Shares outstanding	262,288,607
Primary shares offered in the IPO	50,925,642
Primary shares offered in the follow-on offering	11,550,000
Long-Term Incentive Plan	3,024,625
Repurchase of common shares	(503,642)
Shares outstanding	327,285,232

The number of shares that have been authorised and issued, reduced by treasury shares held. [Refer: Treasury shares]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 79
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_79_a_iv&doctype=Standard
-URIDate 2018-03-16

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant