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Impairment of assets (Tables)

12 Months Ended

Dec. 31, 2020

Disclosure of impairment of assets [Abstract]

Disclosure of significant unobservable inputs used in fair value measurement of assets

The Corporation utilized the Corporation's long-range forecast and the following key assumptions in 2019 compared with 2016 assumptions, which was the most recent detailed valuation:

			2019			2016
Mid-Columbia annual average power prices			US$30 to US$42 per MWh			US$22 to US$46 per MWh
On-highway diesel fuel on coal shipments			US$2.35 to US$2.40 per gallon			US$1.69 to US$2.09 per gallon
Discount rates			5.2 to 6.4 per cent			5.4 to 5.7 per cent

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- Definition

The disclosure of significant inputs for which market data are not available and that are developed using the best information available about the assumptions that market participants would use when measuring the fair value of assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2019-01-01
-Paragraph 93
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2019-en-r&anchor=para_93_d&doctype=Standard
-URIDate 2019-03-27

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X

- Definition

Disclosure of impairment of assets [Abstract]

+ References

No definition available.

+ Details

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