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Pension and other Post-Retirement Benefits - Investment Objectives (Details) - Defined benefits pension plans - CAD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Pension and other PostRetirement Benefits, |  |  |
Employer contributions |  | $ 182 | $ 160
Contribution deposited in solvency reserve account |  | $ 2 | $ 3
Expected cash contributions | $ 172 |  |
Equities |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 48.00% | 56.00%
Equities | Canada |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 13.00% | 18.00%
Equities | United States |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 17.00% | 19.00%
Equities | Foreign |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 18.00% | 19.00%
Fixed income | Canada |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 43.00% | 39.00%
Real estate |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 100.00% | 100.00%
Real estate | Canada |  |  |
Pension and other PostRetirement Benefits, |  |  |
Plan asset allocation percentage |  | 9.00% | 5.00%

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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_147_b&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_148_d_iii&doctype=Standard -URIDate 2018-03-16 + Details
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