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Summary of Significant Accounting Policies (Nature of Operations Narrative) (Details) CAD in Millions | Dec. 31, 2016 CAD MW Customers km | Mar. 22, 2016 | Dec. 31, 2015
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Public Utilities, General Disclosures [Line Items] |  |  |
Indirect Ownership Percentage By Parent | 100.00% |  |
Emera Maine [Member] | Maine |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 157,000 |  |
Nova Scotia Power Inc. [Member] | Nova Scotia [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 511,000 |  |
Emera (Caribbean) Incorporated Parent [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Controlling Interest Ownership Percentage By Parent | 100.00% | 95.50% | 95.50%
Equity Method Investment, Ownership Percentage | 95.50% | 80.70% |
Emera (Caribbean) Incorporated Parent [Member] | Dominica Electricity Services Ltd. [Member] | BAHAMAS |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Controlling Interest Ownership Percentage By Parent | 51.90% |  |
Indirect Ownership Percentage By Parent |  |  | 49.60%
Number Of Cutomers | 36,000 |  |
Emera (Caribbean) Incorporated Parent [Member] | Grand Bahama Power Company Limited [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Controlling Interest Ownership Percentage By Parent | 50.00% |  |
Indirect Ownership Percentage By Parent | 30.40% |  |
Number Of Cutomers | 19,000 |  |
Emera (Caribbean) Incorporated Parent [Member] | St. Lucia Electricity Services Limited [Member] | SAINT LUCIA |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Indirect Ownership Percentage By Parent | 19.10% |  | 18.20%
Emera (Caribbean) Incorporated Parent [Member] | The Barbados Light and Power Company Limited [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 126,000 |  |
Emera Inc | Algonquin Power and Utilities Corporation [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 4.70% |  | 19.60%
Emera Inc | Bayside Power Limited Partnership [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities Property Plant And Equipment Generation Capacity | MW | 290 |  |
Emera Inc | Brooklyn Power Corporation [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities Property Plant And Equipment Generation Capacity | MW | 30 |  |
Emera Inc | Emera Brunswick Pipeline Company Limited [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Length Of Pipeline | km | 145 |  |
Emera Inc | Emera Energy Services [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities Property Plant And Equipment Generation Capacity | MW | 1,115 |  |
Emera Inc | NSP Maritime Link Inc. [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 49.00% |  |
Emera Inc | Bear Swamp Power Company LLC [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities Property Plant And Equipment Generation Capacity | MW | 600 |  |
Emera Inc | Bear Swamp Power Company LLC [Member] | Massachusetts |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 50.00% |  |
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | Emera Newfoundland and Labrador Holdings Inc. [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities Property Plant And Equipment Generation Capacity | MW | 824 |  |
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | Maritimes and Northeast Pipline [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Length Of Pipeline | km | 1,400 |  |
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | Maritimes and Northeast Pipline [Member] | Newfoundland and Labrador [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Controlling Interest Ownership Percentage By Parent | 12.90% |  |
Equity Method Investment, Ownership Percentage |  |  | 12.90%
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | NSP Maritime Link Inc. [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Length Of Pipeline | km | 170 |  |
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | NSP Maritime Link Inc. [Member] | Newfoundland and Labrador [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 100.00% |  |
Public Utilities, Property, Plant and Equipment, Transmission and Distribution | CAD | CAD 1,560 |  |
Emera Newfoundland & Labrador Holdings Inc. Parent [Member] | Labrador-Island Link Limited Partnership [Member] | Newfoundland and Labrador [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 62.70% |  | 55.10%
Public Utilities, Property, Plant and Equipment, Transmission and Distribution | CAD | CAD 3,400 |  |
TECO Energy Inc Parent [Member] | New Mexico Gas Company [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 522,000 |  |
TECO Energy Inc Parent [Member] | Peoples Gas System Division [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 374,000 |  |
TECO Energy Inc Parent [Member] | Tampa Electric Division [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Number Of Cutomers | 736,000 |  |
Icd Utilities Limited Parent [Member] | Grand Bahama Power Company Limited [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 60.70% |  |

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