XML 90 R62.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Common Shares (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Share Capital, Reserves And Other Equity Interest [Abstract] |
Issued and outstanding | TransAlta is authorized to issue an unlimited number of voting common shares without nominal or par value.
As at Dec. 31 | 2018 | 2017
| Common shares (millions) |  | Amount |  | Common shares (millions) |  | Amount |
Issued and outstanding, beginning of year | 287.9 |  | 3,094 |  | 287.9 |  | 3,095 |
Purchased and cancelled under the NCIB | (3.3 | ) | (35 | ) | — |  | — |
| 284.6 |  | 3,059 |  | 287.9 |  | 3,095 |
Amounts receivable under Employee Share Purchase Plan | — |  | — |  | — |  | (1 | )
Issued and outstanding, end of year | 284.6 |  | 3,059 |  | 287.9 |  | 3,094 |
The following are the effects of the Corporation's purchase and cancellation of the common shares during the year ended Dec. 31, 2018:
Total shares purchased(1) |  |  | 3,264,500 |
Average purchase price per share |  |  | $ | 7.02 |
Total cost |  |  | 23 |
Weighted average book value of shares cancelled |  |  | 35 |
Increase to retained earnings |  |  | 12 |
All preferred shares issued and outstanding are non-voting cumulative redeemable fixed rate first preferred shares.
As at Dec. 31 | 2018 | 2017
Series | Number of shares (millions) |  | Amount |  | Number of shares (millions) |  | Amount |
Series A | 10.2 |  | 248 |  | 10.2 |  | 248 |
Series B | 1.8 |  | 45 |  | 1.8 |  | 45 |
Series C | 11.0 |  | 269 |  | 11.0 |  | 269 |
Series E | 9.0 |  | 219 |  | 9.0 |  | 219 |
Series G | 6.6 |  | 161 |  | 6.6 |  | 161 |
Issued and outstanding, end of year | 38.6 |  | 942 |  | 38.6 |  | 942 |
Earnings per share |
Year ended Dec. 31 | 2018 |  | 2017 |  | 2016 |
Net earnings (loss) attributable to common shareholders | (248 | ) | (190 | ) | 117 |
Basic and diluted weighted average number of common shares outstanding (millions) | 287 |  | 288 |  | 288 |
Net earnings (loss) per share attributable to common shareholders, basic and diluted | (0.86 | ) | (0.66 | ) | 0.41 |

X
- Definition The disclosure of classes of share capital. [Refer: Share capital [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DisclosureOfClassesOfShareCapitalExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of earnings per share. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_66&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_EarningsPerShareExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share Capital, Reserves And Other Equity Interest [Abstract] + References No definition available. + Details
Name: | tac_ShareCapitalReservesAndOtherEquityInterestAbstract
Namespace Prefix: | tac_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration