Basis of Presentation of the Consolidated Financial Statements – Investments in Associates (Detail)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Statement Of Compliance And Basis Of Presentation [Line Items]
Percentage of voting power considered to be significant influence	20.00%
GNL Chile S.A. [Member]
Statement Of Compliance And Basis Of Presentation [Line Items]
Direct	0.00%	0.00%
Indirect	33.33%	33.33%
Total	33.33%	33.33%
Energia Marina SpA [Member]
Statement Of Compliance And Basis Of Presentation [Line Items]
Direct	0.00%	0.00%
Indirect	25.00%	25.00%
Total	25.00%	25.00%

The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2019-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_17_b_iii&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2019-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_16_b_iii&doctype=Standard
-URIDate 2019-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2019-01-01
-Paragraph 21
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_21_a_iv&doctype=Standard
-URIDate 2019-03-27

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Balance Type:	na
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