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Non-controlling Interest In Subsidiaries (Non-controlling interest in subsidiaries ) (Details) - CAD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Noncontrolling Interest [Line Items] |  |
Stockholders' Equity Attributable to Noncontrolling Interest | $ 92 | $ 112
Icd Utilities Limited [Member] |  |
Noncontrolling Interest [Line Items] |  |
Stockholders' Equity Attributable to Noncontrolling Interest | 52 | 53
Grand Bahama Power Company Limited [Member] |  |
Noncontrolling Interest [Line Items] |  |
Noncontrolling Interest, Amount Represented by Preferred Stock | 19 | 34
Dominica Electricity Services Ltd. [Member] |  |
Noncontrolling Interest [Line Items] |  |
Stockholders' Equity Attributable to Noncontrolling Interest | $ 21 | $ 25

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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(22)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(24)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of noncontrolling interest in subsidiary represented by preferred securities issued by the subsidiary. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(24)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(22)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: 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(31)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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