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Stock-based Compensation (Employee Common Share Purchase Plan and Dividend Reinvestment Plan) (Details) - CAD ($) |  | 12 Months Ended
--- | --- | ---
Aug. 15, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Employee Common Share Purchase Plan |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Employee Common Share Purchase Plan, Description |  | Eligible employees may participate in Emera’s Employee Common Share Purchase Plan. As of December 31, 2019, the plan allows employees to make cash contributions of a minimum of $25 to a maximum of $8,000 per year for the purpose of purchasing common shares of Emera. The Company also contributes to the plan a percentage of the employees’ contributions. If an employee contributes any amount up to $3,000 to the employee’s plan account, the Company will contribute 20 per cent of that amount. When an employee contributes any amount over $3,000, up to the $8,000 maximum, the Company will contribute 10 per cent of that amount. The plan allows the reinvestment of dividends. |
Defined Contribution Plan, Minimum Annual Contributions Per Employee, Amount |  | $ 25 |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount |  | $ 8,000 |
Maximum aggregate number of common shares reserved for issuance |  | 4,000,000 |
Compensation cost for shares issued |  | $ 1,000,000 | $ 1,000,000
Employee Common Share Purchase Plan | Scenario Plan |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount |  | 20,000 |
Employee Common Share Purchase Plan | Minimum |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount |  | $ 3,000 |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  | 10.00% |
Employee Common Share Purchase Plan | Maximum |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount |  | $ 8,000 |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  | 20.00% |
Dividend Reinvestment Plan |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Employee Common Share Purchase Plan, Description |  | The Company also has a Common Shareholders Dividend Reinvestment and Share Purchase Plan (“Dividend Reinvestment Plan”) or (“DRIP”), which provides an opportunity for shareholders to reinvest dividends and purchase common shares. This plan provides for a discount of up to 5 per cent from the average market price of Emera’s common shares for common shares purchased in connection with the reinvestment of cash dividends. In 2019, the discount was changed from 5 per cent to 2 per cent effective with the dividend payment of August 15, 2019. |
Discount from Market Price, Purchase Date | 2.00% |  |
Dividend Reinvestment Plan | Maximum |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Discount from Market Price, Purchase Date |  | 5.00% |

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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum amount the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition The amount of plan compensation cost recognized during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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- Definition Description of the plan, including the basis for determining contributions, the employee groups covered, and the nature and effect of significant matters affecting comparability of information for all periods presented. For leveraged ESOPs and pension reversion ESOPs, the description generally includes the basis for releasing shares and how dividends on allocated and unallocated shares are used. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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- Definition Discount rate from fair value on purchase date that participants pay for shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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