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Variable Interest Entities (Details) - Emera Inc - NSP Maritime Link Inc. [Member] - Available-for-sale Investment and Restricted Cash [Member] - CAD CAD in Millions | Dec. 31, 2016 | Dec. 31, 2015
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Variable Interest Entity [Line Items] |  |
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets | CAD 315 | CAD 188
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount | CAD 577 | CAD 1,007

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- Definition The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5747-111685 + Details
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Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph a -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685 + Details
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- Details
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- Details
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- Details
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