Long-Term Debt (Summary of Long-Term Debt, Revolving Credit Facilities, Outstanding Borrowings and Available Capacity) (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Debt issuance costs	$ (125)	$ (126)
Amount due within one year	(676)	(574)
Long Term Debt, Adjustments	(801)	(698)
Long-Term Debt	17,689	15,744
Interest expense	109	110
Emera
Debt Instrument [Line Items]
Long-term debt	2,552	2,528
NMGC
Debt Instrument [Line Items]
Long-term debt	672	629
NSPI
Debt Instrument [Line Items]
Long-term debt	3,886	3,546
ECI
Debt Instrument [Line Items]
Long-term debt	422	449
TECO Energy
Debt Instrument [Line Items]
Fair market value adjustment	$ 0	$ 2
Bankers acceptances \| SOFR loans \| Emera
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2027
Long-term debt	$ 465	$ 403
Unsecured fixed rate notes \| Emera
Debt Instrument [Line Items]
Weighted average interest rate	4.84%	2.90%
Maturity	2030
Long-term debt	$ 500	$ 500
Unsecured fixed rate notes \| Emera Finance
Debt Instrument [Line Items]
Maturity	2024 - 2046
Fixed to floating subordinated notes \| Emera
Debt Instrument [Line Items]
Weighted average interest rate	6.75%	6.75%
Maturity	2076
Long-term debt	$ 1,587	$ 1,625
Unsecured senior notes \| Emera Finance
Debt Instrument [Line Items]
Weighted average interest rate	3.65%	3.65%
Long-term debt	$ 3,637	$ 3,725
Fixed rate notes and bonds \| TEC
Debt Instrument [Line Items]
Weighted average interest rate	4.61%	4.15%
Maturity	2024 - 2051
Long-term debt	$ 5,654	$ 4,341
Fixed rate notes and bonds \| PGS
Debt Instrument [Line Items]
Weighted average interest rate	5.63%	3.78%
Maturity	2028 - 2053
Long-term debt	$ 1,223	$ 772
Fixed rate notes and bonds \| NMGC
Debt Instrument [Line Items]
Weighted average interest rate	3.78%	3.11%
Maturity	2026 - 2051
Long-term debt	$ 642	$ 521
Fixed rate notes and bonds \| NMGI
Debt Instrument [Line Items]
Weighted average interest rate	3.64%	3.64%
Maturity	2024
Long-term debt	$ 198	$ 203
Discount notes \| NSPI
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2024 - 2027
Long-term debt	$ 721	$ 881
Medium term fixed rate notes \| NSPI
Debt Instrument [Line Items]
Weighted average interest rate	5.13%	5.14%
Maturity	2025 - 2097
Long-term debt	$ 3,165	$ 2,665
Senior secured credit facility \| EBP
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2026
Long-term debt	$ 246	$ 249
Amortizing fixed rate notes \| ECI
Debt Instrument [Line Items]
Weighted average interest rate	4.00%	3.97%
Maturity	2026
Long-term debt	$ 79	$ 100
Secured senior notes \| ECI
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2027
Long-term debt	$ 75	$ 86
Secured fixed rate senior notes \| ECI
Debt Instrument [Line Items]
Weighted average interest rate	3.09%	3.06%
Maturity	2024 - 2029
Long-term debt	$ 84	$ 142
Non-revolving term facility, floating rate \| NMGC
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2024
Long-term debt	$ 30	$ 108
Non-revolving term facility, floating rate \| ECI
Debt Instrument [Line Items]
Interest Rate Terms	Variable	Variable
Maturity	2025
Long-term debt	$ 29	$ 30
Non-revolving term facility, fixed rate \| ECI
Debt Instrument [Line Items]
Weighted average interest rate	2.15%	2.05%
Maturity	2025 - 2027
Long-term debt	$ 155	$ 91

The amount of adjustments made to long term debt.

No definition available.

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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.

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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.

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- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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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.

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- Definition

Aggregate amount of interest expense on all borrowings.

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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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