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Non-controlling Interest In Subsidiaries (Preferred Shares Authorized) (Details) - CAD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Noncontrolling Interest [Line Items] |  |
Number of shares issued and outstanding | 29,000,000 | 29,000,000
Grand Bahama Power Company Limited [Member] | Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares [Member] |  |
Noncontrolling Interest [Line Items] |  |
Preferred Stock, Shares Authorized | 35,000 |
Number of shares issued and outstanding | 20,000 | 35,000
Preferred Stock Value Outstanding | $ 19 | $ 34

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- Definition Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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