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Non-controlling Interest In Subsidiaries (Preferred Shares Authorized) (Details) - CAD CAD in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Noncontrolling Interest [Line Items] |  |
Number of shares issued and outstanding | 29,000,000 | 29,000,000
Nova Scotia Power Inc. [Member] |  |
Noncontrolling Interest [Line Items] |  |
Preferred Stock, Shares Authorized, Unlimited | Unlimited |
Number of shares issued and outstanding | 0 | 0
Preferred Stock Value Outstanding | CAD 0.0 | CAD 0.0
Grand Bahama Power Company Limited [Member] | Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares [Member] |  |
Noncontrolling Interest [Line Items] |  |
Preferred Stock, Shares Authorized | 35,000,000,000 |
Number of shares issued and outstanding | 35,000,000,000 | 35,000,000,000
Preferred Stock Value Outstanding | CAD 34.0 | CAD 34.0

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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + 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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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + 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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- 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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