Long Term Debt (Long-term Debt) (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Fair Market Value Adjustments to Debt	$ 22	$ 31
Debt issuance costs	(113)	(98)
Amount due within one year	(1,119)	(741)
Long Term Debt, Adjustments	(1,210)	(808)
Long-term Debt and Capital Lease Obligations	14,292	13,140
Emera Inc
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 2,701	2,363
Emera Inc \| Bankers Acceptances, LIBOR Loans [Member]
Debt Instrument [Line Items]
Variable rate	Variable
Long-term Debt, Gross	$ 339	$ 133
Emera Inc \| Bankers Acceptances, LIBOR Loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2020
Emera Inc \| Unsecured fixed rate notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.50%	3.50%
Long-term Debt, Gross	$ 725	$ 725
Emera Inc \| Unsecured fixed rate notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2019
Emera Inc \| Unsecured fixed rate notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2023
Emera Inc \| Fixed to floating subordinated notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	6.75%
Long-term Debt, Gross	$ 1,637	$ 1,505
Emera Inc \| Fixed to floating subordinated notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2076
Affiliated Entity [Member] \| Fixed to floating subordinated notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate		6.75%
Emera US Finance LP [Member] \| Unsecured senior notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.60%	3.60%
Long-term Debt, Gross	$ 4,434	$ 4,077
Emera US Finance LP [Member] \| Unsecured senior notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2019
Emera US Finance LP [Member] \| Unsecured senior notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2046
TECO Finance, Inc. [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 409	690
TECO Finance, Inc. [Member] \| Variable rate notes [Member]
Debt Instrument [Line Items]
Variable rate	Variable
Long-term Debt, Gross	$ 0	$ 314
TECO Finance, Inc. [Member] \| Variable rate notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2018
TECO Finance, Inc. [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.15%	5.15%
Long-term Debt, Gross	$ 409	$ 376
TECO Finance, Inc. [Member] \| Fixed rate notes and bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jan. 01, 2020
Tampa Electric Division [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.64%	4.75%
Long-term Debt, Gross	$ 3,126	$ 2,410
Tampa Electric Division [Member] \| Fixed rate notes and bonds [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2021
Tampa Electric Division [Member] \| Fixed rate notes and bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2049
Peoples Gas System Division [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.66%	5.06%
Long-term Debt, Gross	$ 425	$ 328
Peoples Gas System Division [Member] \| Fixed rate notes and bonds [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2021
Peoples Gas System Division [Member] \| Fixed rate notes and bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2049
New Mexico Gas Company [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.53%	4.53%
Long-term Debt, Gross	$ 368	$ 339
New Mexico Gas Company [Member] \| Fixed rate notes and bonds [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2021
New Mexico Gas Company [Member] \| Fixed rate notes and bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2026
New Mexico Gas Incorporate [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.41%	3.41%
Long-term Debt, Gross	$ 273	$ 251
New Mexico Gas Incorporate [Member] \| Fixed rate notes and bonds [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2019
New Mexico Gas Incorporate [Member] \| Fixed rate notes and bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2024
Nova Scotia Power Inc. [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 2,576	2,424
Nova Scotia Power Inc. [Member] \| Discount notes [Member]
Debt Instrument [Line Items]
Variable rate	Variable
Long-term Debt, Gross	$ 516	$ 364
Nova Scotia Power Inc. [Member] \| Discount notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jan. 01, 2023
Nova Scotia Power Inc. [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.73%	5.73%
Long-term Debt, Gross	$ 1,965	$ 1,965
Nova Scotia Power Inc. [Member] \| Medium-term Notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2025
Nova Scotia Power Inc. [Member] \| Medium-term Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2097
Nova Scotia Power Inc. [Member] \| Fixed rate debenture [Member]
Debt Instrument [Line Items]
Weighted average interest rate	9.75%	9.75%
Long-term Debt, Gross	$ 95	$ 95
Nova Scotia Power Inc. [Member] \| Fixed rate debenture [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2019
Emera Maine [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 478	408
Emera Maine [Member] \| LIBOR loans and demand loans [Member]
Debt Instrument [Line Items]
Variable rate	Variable
Long-term Debt, Gross	$ 28	$ 51
Emera Maine [Member] \| LIBOR loans and demand loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jan. 01, 2023
Emera Maine [Member] \| Secured fixed rate mortgage bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	9.74%	9.74%
Long-term Debt, Gross	$ 68	$ 63
Emera Maine [Member] \| Secured fixed rate mortgage bonds [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2020
Emera Maine [Member] \| Secured fixed rate mortgage bonds [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2022
Emera Maine [Member] \| Unsecured senior fixed rate notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.23%	4.15%
Long-term Debt, Gross	$ 382	$ 294
Emera Maine [Member] \| Unsecured senior fixed rate notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2022
Emera Maine [Member] \| Unsecured senior fixed rate notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2048
Emera Brunswick Pipeline Company Limited [Member] \| Senior secured credit facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.08%	3.08%
Long-term Debt, Gross	$ 248	$ 248
Debt Instrument, Maturity Date	Jan. 01, 2022
Grand Bahama Power Company Limited [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 182	$ 166
Grand Bahama Power Company Limited [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	7.07%	7.07%
Long-term Debt, Gross	$ 68	$ 88
Grand Bahama Power Company Limited [Member] \| Senior Notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2020
Grand Bahama Power Company Limited [Member] \| Senior Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2023
Grand Bahama Power Company Limited [Member] \| Unsecured amortizing fixed rate notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.83%	3.77%
Long-term Debt, Gross	$ 114	$ 78
Grand Bahama Power Company Limited [Member] \| Unsecured amortizing fixed rate notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2021
Grand Bahama Power Company Limited [Member] \| Unsecured amortizing fixed rate notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2022
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 258	244
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member] \| Secured senior notes [Member]
Debt Instrument [Line Items]
Variable rate	Variable
Long-term Debt, Gross	$ 159	$ 168
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member] \| Secured senior notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2021
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member] \| Secured fixed rate senior notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.74%	5.06%
Long-term Debt, Gross	$ 99	$ 76
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member] \| Secured fixed rate senior notes [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2020
The Barbados Light & Power Company Limited And Emera Caribbean Incorporated [Member] \| Secured fixed rate senior notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 31, 2035
Icd Utilities Limited [Member] \| Fixed rate notes and bonds [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.00%	0.00%
Long-term Debt, Gross	$ 24	$ 0

Fair market value adjustments to debt.

No definition available.

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- Definition

Adjustments made to long term debt.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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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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Data Type:	xbrli:stringItemType
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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
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Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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- Definition

Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

+ References

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