Short Term Debt (Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity) (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Total available capacity	$ 3,155	$ 2,729
Total advances under available facilities	2,735	1,739
Available capacity under existing agreements	$ 420	990
Term credit facility \| TEC
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2023
Total available capacity	$ 542	634
Revolving credit facility \| TECO Energy/TECO Finance
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2026
Total available capacity	$ 542	507
Revolving credit facility \| TEC
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2026
Total available capacity	$ 1,084	1,014
Revolving credit facility \| NMGC
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2026
Total available capacity	$ 169	158
Revolving credit facility \| GBPC
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	on demand
Total available capacity	$ 18	16
Non-revolving term loan \| Emera Inc.
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2023
Total available capacity	$ 400	400
Non-revolving term loan II \| Emera Inc.
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Maturity	2023
Total available capacity	$ 400	0
Advances under revolving credit and term facilities
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Total advances under available facilities	2,731	1,735
Letters of credit issued within the credit facilities
Short-term revolving and non-revolving credit facilities, outstanding borrowings and available capacity
Total advances under available facilities	$ 4	$ 4

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
-Paragraph 1
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