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Commitments and Contingencies (Legal Proceedings) (Details) $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018	Dec. 31, 2019 CAD ($)	Dec. 31, 2019 USD ($)
Prime Rate [Member] | Tampa Electric
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss			$ 27	$ 21
Prime Rate [Member] | TGH
Loss Contingencies [Line Items]
Litigation Settlement, Amount	$ 21
Litigation Settlement Variable Rate	2.00%
Prime Rate [Member] | Maximum | Emera Maine
Loss Contingencies [Line Items]
Public Utilities, Approved Return on Equity, Percentage		10.41%
ISO-New England Open Access Transmission Tariff-allowed | Emera Maine
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss				$ 4
ISO-New England Open Access Transmission Tariff-allowed | Prime Rate [Member] | Emera Maine
Loss Contingencies [Line Items]
Public Utilities, Approved Return on Equity, Percentage		10.57%
ISO-New England Open Access Transmission Tariff-allowed | Prime Rate [Member] | Maximum | Emera Maine
Loss Contingencies [Line Items]
Public Utilities, Approved Return on Equity, Percentage		11.74%

X

- Definition

Variable rate based on the ligation settlement.

+ References

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Amount awarded to other party in judgment or settlement of litigation.

+ References

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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-Section 50
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Percentage of public utility's approved return on equity.

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