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Summary of Significant Accounting Policies (Intangible Assets) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 CAD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |
2017 | $ 8
2018 | 8
2019 | 8
2020 | 8
2021 | 8
Computer Software, Intangible Asset [Member] |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |
2017 | 6
2018 | 6
2019 | 6
2020 | 6
2021 | 6
Use Rights [Member] |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |
2017 | 1
2018 | 1
2019 | 1
2020 | 1
2021 | 1
Naming Rights [Member] |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |
2017 | 1
2018 | 1
2019 | 1
2020 | 1
2021 | $ 1
Minimum [Member] | Computer Software, Intangible Asset [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 3 years
Minimum [Member] | Use Rights [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 50 years
Minimum [Member] | Naming Rights [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 1 year
Maximum [Member] | Computer Software, Intangible Asset [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 15 years
Maximum [Member] | Use Rights [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 143 years
Maximum [Member] | Naming Rights [Member] |
Finite-Lived Intangible Assets [Line Items] |
Finite-Lived Intangible Asset, Useful Life | 24 years

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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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