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Summary of Significant Accounting Policies (Nature of Operations) (Narrative) (Details) $ in Billions | 2 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 05, 2019 | Mar. 29, 2019 | Dec. 31, 2019 CAD ($) MW Customers km | Dec. 20, 2019
EUS | Disposition |  |  |  |
Nature of operations [Line items] |  |  |  |
Disposition, Name |  |  |  | EUS
Description and Timing and Disposition |  |  |  | EUS ceased operations on September 30, 2019
New England Gas Generating Facilities | Disposition |  |  |  |
Nature of operations [Line items] |  |  |  |
Disposition, Name |  | New England Gas Generation |  |
Description and Timing and Disposition |  | The NEGG assets were classified as held for sale at December 31, 2018 and the Company ceased depreciation of these assets on November 27, 2018. |  |
Segment that Includes Disposition |  | Other reportable segment |  |
Bayside Power Limited Partnership | Disposition |  |  |  |
Nature of operations [Line items] |  |  |  |
Disposition, Name | Bayside facility |  |  |
Segment that Includes Disposition | Other reportable segment |  |  |
Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera’s investments in other energy-related non-regulated companies (included within the Other reportable segment) include the following: Emera Energy, which consists of: Emera Energy Services (“EES”), a physical energy business that purchases and sells natural gas and electricity and provides related energy asset management services; Brooklyn Power Corporation (“Brooklyn Energy”), a 30 MW biomass co-generation electricity facility in Brooklyn, Nova Scotia; and a 50.0 per cent joint venture interest in Bear Swamp Power Company LLC (“Bear Swamp”), a 600 MW pumped storage hydroelectric facility in northwestern Massachusetts. Emera Reinsurance Limited, a captive insurance company providing insurance and reinsurance to Emera and certain affiliates, to enable more cost-efficient management of risk and deductible levels across Emera; Emera US Finance LP (“Emera Finance”) and TECO Finance, Inc. (“TECO Finance”), financing subsidiaries of Emera; Emera US Holdings Inc., a wholly owned holding company for certain of Emera’s assets located in the United States; and other investments. |
Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment that Includes Disposition |  |  | Other Electric Utilities |
Operating | Other Electric Utilities | Held for sale |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | , a regulated electric transmission and distribution utility, serving approximately 159,000 customers in the state of Maine. On March 25, 2019, Emera announced an agreement to sell Emera Maine. The transaction is expected to close in early 2020, subject to approval of the Maine Public Utilities Commission (“MPUC”). |
Number of Customers |  |  | 159,000 |
Disposition, Name |  |  | Emera Maine |
Description and Timing and Disposition |  |  | On March 25, 2019, Emera announced an agreement to sell Emera Maine. The transaction is expected to close in early 2020, subject to approval of the Maine Public Utilities Commission (“MPUC”) |
Operating | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | At December 31, 2019, Emera’s investments in other energy-related non-regulated companies (included within the Other reportable segment) include the following: Emera Energy, which consists of: Emera Energy Services (“EES”), a physical energy business that purchases and sells natural gas and electricity and provides related energy asset management services; Brooklyn Power Corporation (“Brooklyn Energy”), a 30 MW biomass co-generation electricity facility in Brooklyn, Nova Scotia; and a 50.0 per cent joint venture interest in Bear Swamp Power Company LLC (“Bear Swamp”), a 600 MW pumped storage hydroelectric facility in northwestern Massachusetts. Emera Reinsurance Limited, a captive insurance company providing insurance and reinsurance to Emera and certain affiliates, to enable more cost-efficient management of risk and deductible levels across Emera; Emera US Finance LP (“Emera Finance”) and TECO Finance, Inc. (“TECO Finance”), financing subsidiaries of Emera; Emera US Holdings Inc., a wholly owned holding company for certain of Emera’s assets located in the United States; and other investments. |
Maritimes and Northeast Pipline | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 12.90% |
St. Lucia Electricity Services Limited | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 19.10% |
Dominica Electricity Services Ltd. | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 51.90% |
Number of Customers |  |  | 31,000 |
Tampa Electric | Operating | Florida Electric Utility |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Tampa Electric, a vertically integrated regulated electric utility, serving approximately 779,000 customers in West Central Florida |
Number of Customers |  |  | 779,000 |
Nova Scotia Power Inc. | Operating | Canadian Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Nova Scotia Power Inc. (“NSPI”), a vertically integrated regulated electric utility and the primary electricity supplier in Nova Scotia, serving approximately 523,000 customers |
Number of Customers |  |  | 523,000 |
Emera Newfoundland and Labrador Holdings Inc. | Operating | Canadian Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera Newfoundland & Labrador Holdings Inc. (“ENL”), consisting of two transmission investments related to an 824 megawatt (“MW”) hydroelectric generating facility at Muskrat Falls on the Lower Churchill River in Labrador being developed by Nalcor Energy and forecasted to be generating full power in the second half of 2020. ENL’s two investments are: a 100 per cent investment in NSP Maritime Link Inc. (“NSPML”), which developed the Maritime Link Project, a $1.6 billion transmission project, including two 170-kilometre sub-sea cables, connecting the island of Newfoundland and Nova Scotia. This project went in service on January 15, 2018; and a ##D<LIL_%Ownership> per cent investment in the partnership capital of Labrador-Island Link Limited Partnership (“LIL”), a $3.7 billion electricity transmission project in Newfoundland and Labrador to enable the transmission of Muskrat Falls energy between Labrador and the island of Newfoundland. Construction of the LIL has been completed and Nalcor recognized the first flow of energy from Labrador to Newfoundland in June 2018. Nalcor continues to work towards commissioning the LIL, which is forecasted to be in 2020. |
Public Utilities Property Plant And Equipment Generation Capacity | MW |  |  | 824 |
Emera Newfoundland and Labrador Holdings Inc. | NSP Maritime Link Inc. | Operating | Canadian Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 100.00% |
Public Utilities, Equipment, Transmission and Distribution | $ |  |  | $ 1.6 |
Length Of Pipeline | km |  |  | 170 |
Emera Newfoundland and Labrador Holdings Inc. | Labrador-Island Link Limited Partnership | Operating | Canadian Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 49.50% |
Public Utilities, Equipment, Transmission and Distribution | $ |  |  | $ 3.7 |
Emera (Caribbean) Incorporated | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera (Caribbean) Incorporated (“ECI”), a holding company with regulated electric utilities that include: The Barbados Light & Power Company Limited (“BLPC”), a vertically integrated regulated electric utility on the island of Barbados, serving approximately 131,000 customers; Grand Bahama Power Company Limited (“GBPC”), a vertically integrated regulated electric utility on Grand Bahama Island, serving approximately 18,000 customers. On September 1, 2019, Grand Bahama Island was struck by Hurricane Dorian, causing significant damage. Refer to note ##NRM and ##NGW for further details; a 51.9 per cent interest in Dominica Electricity Services Ltd. (“Domlec”), a vertically integrated regulated electric utility on the island of Dominica, serving approximately 31,000 customers; and a 19.1 per cent equity interest in St. Lucia Electricity Services Limited (“Lucelec”), a vertically integrated regulated electric utility on the island of St. Lucia. |
Barbados Light and Power Company Limited | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | The Barbados Light & Power Company Limited (“BLPC”), a vertically integrated regulated electric utility on the island of Barbados, serving approximately 131,000 customers; |
Number of Customers |  |  | 131,000 |
Grand Bahama Power Company Limited | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Grand Bahama Power Company Limited (“GBPC”), a vertically integrated regulated electric utility on Grand Bahama Island, serving approximately 18,000 customers. On September 1, 2019, Grand Bahama Island was struck by Hurricane Dorian, causing significant damage. Refer to note ##NRM and ##NGW for further details; |
Number of Customers |  |  | 18,000 |
Dominica Electricity Services Ltd. | Operating | Other Electric Utilities |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | a 51.9 per cent interest in Dominica Electricity Services Ltd. (“Domlec”), a vertically integrated regulated electric utility on the island of Dominica, serving approximately 31,000 customers |
Peoples Gas System Division |  |  |  |
Nature of operations [Line items] |  |  |  |
Length Of Pipeline | km |  |  | 800 |
Peoples Gas System Division | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Number of Customers |  |  | 406,000 |
Peoples Gas System Division | Operating | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Peoples Gas System (“PGS”), a regulated gas distribution utility, serving approximately 406,000 customers across Florida; |
New Mexico Gas Company | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Number of Customers |  |  | 534,000 |
New Mexico Gas Company | Operating | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | New Mexico Gas Company, Inc. (“NMGC”), a regulated gas distribution utility, serving approximately 534,000 customers in New Mexico; |
SeaCoast Gas Transmission, LLC | Operating | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | SeaCoast Gas Transmission, LLC (“SeaCoast”), a regulated intrastate natural gas transmission company offering services in Florida |
Emera Brunswick Pipeline Company Limited | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Length Of Pipeline | km |  |  | 145 |
Public Utilities, Property, Plant and Equipment, Distribution, Useful Life |  |  | 25 years |
Emera Brunswick Pipeline Company Limited | Operating | Gas Utilities and Infrastructure |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera Brunswick Pipeline Company Limited (“Brunswick Pipeline”), a 145-kilometre pipeline delivering re-gasified liquefied natural gas (“LNG”) from Saint John, New Brunswick to the United States border under a 25-year firm service agreement with Repsol Energy Canada, which expires in 2034 |
Emera Energy | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera Energy Services (“EES”), a physical energy business that purchases and sells natural gas and electricity and provides related energy asset management services; Brooklyn Power Corporation (“Brooklyn Energy”), a 30 MW biomass co-generation electricity facility in Brooklyn, Nova Scotia; and a 50.0 per cent joint venture interest in Bear Swamp Power Company LLC (“Bear Swamp”), a 600 MW pumped storage hydroelectric facility in northwestern Massachusetts. |
Emera Energy | Bear Swamp Power Company LLC | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Equity Method Investment, Ownership Percentage |  |  | 50.00% |
Public Utilities Property Plant And Equipment Generation Capacity | MW |  |  | 600 |
Emera Energy Services | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera Energy Services (“EES”), a physical energy business that purchases and sells natural gas and electricity and provides related energy asset management services; |
Brooklyn Power Corporation | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Brooklyn Power Corporation (“Brooklyn Energy”), a 30 MW biomass co-generation electricity facility in Brooklyn, Nova Scotia; |
Emera Reinsurance Limited | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera Reinsurance Limited, a captive insurance company providing insurance and reinsurance to Emera and certain affiliates, to enable more cost-efficient management of risk and deductible levels across Emera; |
Emera US Finance LP | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | financing subsidiaries of Emera; |
TECO Finance, Inc. | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | financing subsidiaries of Emera; |
Emera US Holdings Inc. | Other |  |  |  |
Nature of operations [Line items] |  |  |  |
Segment Reporting, Additional Information about Entity's Reportable Segments |  |  | Emera US Holdings Inc., a wholly owned holding company for certain of Emera’s assets located in the United States; and |

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