XML 83 R107.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Income Taxes - Aggregate Current and Deferred Income Tax Charged to Equity (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Abstract]
Net impact related to cash flow hedges	$ 6	$ (12)	$ (108)
Net impact related to net investment hedges	0	0	(7)
Net actuarial gains (losses)	(7)	5	(4)
Income tax expense reported in equity	$ (1)	$ (7)	$ (119)

X

- Definition

The aggregate current and deferred tax relating to particular items that are charged or credited directly to equity, for example: (a) an adjustment to the opening balance of retained earnings resulting from either a change in accounting policy that is applied retrospectively or the correction of an error; and (b) amounts arising on initial recognition of the equity component of a compound financial instrument. [Refer: Deferred tax relating to items credited (charged) directly to equity; Retained earnings; Financial instruments, class [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2018-01-01
-Paragraph 81
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_a&doctype=Standard
-URIDate 2018-03-16

+ Details

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

X

- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2018-01-01
-Paragraph 81
-Subparagraph ab
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_ab&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_90&doctype=Standard
-URIDate 2018-03-16

+ Details

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

X

- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to remeasurements of defined benefit plans. [Refer: Other comprehensive income; Reserve of remeasurements of defined benefit plans; Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2018-01-01
-Paragraph 81
-Subparagraph ab
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_ab&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_90&doctype=Standard
-URIDate 2018-03-16

+ Details

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

X

- Definition

Income Taxes [Abstract]

+ References

No definition available.

+ Details

Name:	tac_IncomeTaxesAbstract
Namespace Prefix:	tac_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Income tax relating to hedges of investments in equity instruments

+ References

No definition available.

+ Details

Name:	tac_Incometaxrelatingtohedgesofinvestmentsinequityinstruments
Namespace Prefix:	tac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration