XML 87 R59.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Decommissioning and Other Provisions (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Other Provisions, Contingent Liabilities And Contingent Assets [Abstract] |
Change in decommissioning and other provision balances | The change in decommissioning and other provision balances is as follows:
| Decommissioning and restoration |  | Other |  | Total |
Balance, Dec. 31, 2016 | 293 |  | 50 |  | 343 |
Liabilities incurred | 3 |  | 19 |  | 22 |
Liabilities settled | (19 | ) | (31 | ) | (50 | )
Liabilities disposed(1) | (8 | ) | — |  | (8 | )
Accretion | 23 |  | — |  | 23 |
Revisions in estimated cash flows(2) | 41 |  | 1 |  | 42 |
Revisions in discount rates(2) | 110 |  | — |  | 110 |
Reversals | — |  | (4 | ) | (4 | )
Change in foreign exchange rates | (6 | ) | (2 | ) | (8 | )
Balance, Dec. 31, 2017 | 437 |  | 33 |  | 470 |
Liabilities incurred | 5 |  | 17 |  | 22 |
Liabilities settled | (31 | ) | (10 | ) | (41 | )
Accretion | 24 |  | — |  | 24 |
Acquisition of liabilities (Big Level) |  | 8 |  | 8 |
Revisions in estimated cash flows | 2 |  | 3 |  | 5 |
Revisions in discount rates | (37 | ) | — |  | (37 | )
Reversals | — |  | (5 | ) | (5 | )
Change in foreign exchange rates | 7 |  | 3 |  | 10 |
Balance, Dec. 31, 2018 | 407 |  | 49 |  | 456 |
(1) Relates to the disposition of the Solomon power station and the sale of the Wintering Hills wind facility. (2) During 2017, mainly as a result of the OCA (see Note 4(O)), the discount rates used for the Canadian coal and mining operations decommissioning provisions were changed to the use of 5 to 15-year rates. The use of lower, shorter-term discount rates increased the corresponding liabilities. On average, these rates decreased by approximately 1.60 to 2.10 per cent. Additionally, the amount and timing of cash outflows for certain Canadian coal plants and mining operations was also revised, resulting in an increase to the corresponding liabilities.
| Decommissioning and restoration |  | Other |  | Total |
Balance, Dec. 31, 2017 | 437 |  | 33 |  | 470 |
Current portion | 40 |  | 27 |  | 67 |
Non-current portion | 397 |  | 6 |  | 403 |
Balance, Dec. 31, 2018 | 407 |  | 49 |  | 456 |
Current portion | 35 |  | 35 |  | 70 |
Non-current portion | 372 |  | 14 |  | 386 |

X
- Definition The disclosure of 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 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_84&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DisclosureOfOtherProvisionsExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Other Provisions, Contingent Liabilities And Contingent Assets [Abstract] + References No definition available. + Details
Name: | tac_OtherProvisionsContingentLiabilitiesAndContingentAssetsAbstract
Namespace Prefix: | tac_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration