XML 108 R80.htm IDEA: XBRL DOCUMENT v3.10.0.1

Significant Events - Force Majeure Relief (Details) - CAD ($) $ in Millions		12 Months Ended
	Nov. 18, 2016	Dec. 31, 2018	Dec. 31, 2017
Disclosure of other provisions [line items]
Reversal of unused provision		$ (5)	$ (4)
Force Majeure Relief Claim
Disclosure of other provisions [line items]
Reversal of unused provision	$ 94

X

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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

X

- Definition

The amount reversed for unused other provisions. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 37
-IssueDate 2017-01-01
-Paragraph 84
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_84_d&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	ifrs-full_ClassesOfProvisionsAxis=tac_ForceMajeureReliefClaimMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: