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Summary of Significant Accounting Policies (Nature of Operations Narrative) (Details) $ in Millions | Dec. 31, 2017 CAD ($) MW Customers km
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Emera Maine [Member] | Maine |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 158,000
Nova Scotia Power Inc. [Member] | Nova Scotia [Member] |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 515,000
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%
Number Of Customers | 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 Customers | 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%
Emera (Caribbean) Incorporated Parent [Member] | The Barbados Light and Power Company Limited [Member] |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 129,000
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 | 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%
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 | $ | $ 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 | 49.50%
Public Utilities, Property, Plant and Equipment, Transmission and Distribution | $ | $ 3,700
TECO Energy Inc Parent [Member] | New Mexico Gas Company [Member] |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 525,000
TECO Energy Inc Parent [Member] | Peoples Gas System Division [Member] |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 375,000
TECO Energy Inc Parent [Member] | Tampa Electric Division [Member] |
Public Utilities, General Disclosures [Line Items] |
Number Of Customers | 750,000
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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