Nature of the business, Assets acquired (Details) $ in Millions	Feb. 28, 2018 USD ($) MW	Jul. 30, 2015
Kaxu [Member]
Nature of the business [Abstract]
Percentage interest acquired		51.00%
Mini- Hydro [Member]
Nature of the business [Abstract]
Percentage interest acquired	100.00%
Gross capacity \| MW	4
Acquisition purchase price \| $	$ 9

The maximum, or rated, power generation capacity, in MW, of power facility or group of facilities, without adjusting for the facility's power parasitic consumption.

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B64_f&doctype=Appendix&seq=2
-URIDate 2017-03-09

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- Definition

The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B64_c&doctype=Appendix&seq=2
-URIDate 2017-03-09

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- Details

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- Details

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