The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ 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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- Definition

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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ 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))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Short Term Debt (Narrative) (Details) $ in Millions, $ in Millions	Jan. 29, 2021	Dec. 18, 2020 USD ($)	Dec. 01, 2020 CAD ($)	Jun. 30, 2020 USD ($)	Apr. 03, 2020 USD ($)	Feb. 28, 2020 USD ($)	Feb. 06, 2020 USD ($)	Dec. 31, 2020 CAD ($)	Dec. 31, 2019 CAD ($)
Line of Credit Facility [Line Items]
Weighted average interest rate								1.01%	2.54%
Line of Credit Facility, Maximum Borrowing Capacity								$ 2,677	$ 2,463
Letters of Credit Outstanding, Amount								4	3
TECO Energy/TECO Finance
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								0	649
Revolving credit facility \| TEC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								1,019	520
Revolving credit facility \| NMGC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								159	162
Revolving credit facility \| TECO Energy/TECO Finance
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								509	520
Term loan credit facility \| TEC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								$ 382	$ 0
Non-revolving credit agreement \| TEC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 300
Line of Credit Facility, Expiration Date							Feb. 04, 2021
Non-revolving credit agreement \| TEC \| Extended Maturity [Member] \| Subsequent Event [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Date	Apr. 29, 2021
Non-revolving credit agreement \| Emera Inc.
Line of Credit Facility [Line Items]
Weighted average interest rate								0.94%	2.69%
Line of Credit Facility, Maximum Borrowing Capacity			$ 400					$ 400	$ 400
Line of Credit Facility, Expiration Date			Dec. 15, 2020
Non-revolving credit agreement \| Emera Inc. \| Extended Maturity [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Date			Dec. 16, 2021
Bank credit facility [Member] \| TEC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 400
Increased commitment		$ 800
Line of Credit Facility, Expiration Date		Mar. 22, 2022
Letters of Credit Outstanding, Amount		$ 80
Bank credit facility [Member] \| TEC \| Extended Maturity [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Date		Mar. 22, 2023
Bank credit facility [Member] \| NMGC
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 125
Line of Credit Facility, Expiration Date		Mar. 22, 2022
Letters of Credit Outstanding, Amount		$ 30
Bank credit facility [Member] \| NMGC \| Extended Maturity [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Date		Mar. 22, 2023
Bank credit facility [Member] \| TECO Finance
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 400				$ 500
Line of Credit Facility, Expiration Date		Mar. 22, 2022				Mar. 05, 2020
Repayments of credit facility				$ 300	$ 200
Letters of Credit Outstanding, Amount		$ 50
Bank credit facility [Member] \| TECO Finance \| Extended Maturity [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Date		Mar. 22, 2023				Jul. 03, 2020