Excess fuel recvoery payable to customers.

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Amount of recovery and settlement amount for public utilities.

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Actual contribution amount from third party based on the settlement amount for public utilities.

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Amount of minimum contributions from third party based on the settlement amount for public utilities.

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The total amount of allowable costs capitalized during the period by the entity pertaining to Phase-In plans which were deferred on the expectation of future recovery.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44264-110382

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Percentage of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved return on equity.

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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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Percentage of public utility's requested equity to capital, including debt and equity.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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-Name Accounting Standards Codification
-Topic 980
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-Paragraph 1
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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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-Name Accounting Standards Codification
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-SubTopic 405
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-Paragraph 1
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Regulatory Assets and Liabilities (ROE of NSPI) (Details) - CAD ($) $ in Millions			12 Months Ended
	Nov. 29, 2016	Jul. 19, 2016	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Public Utilities, General Disclosures [Line Items]
Phase-in Plan, Amount of Costs Deferred for Rate-making Purposes					$ 53
Regulatory Liabilities					2,610	$ 2,468
Regulatory Assets					$ 1,569	$ 1,411
Public Utilities Act of Nova Scotia [Member] \| Scenario, Forecast [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Settlement Amount				$ 111
Nova Scotia Power Inc. [Member] \| Fuel Adjustment Mechanism Asset [Member]
Public Utilities, General Disclosures [Line Items]
Regulated common equity component					40.00%
Nova Scotia Power Inc. [Member] \| Rate Stability Plan fuel costs for 2017 through 2019 [Member] \| Fuel Adjustment Mechanism Asset [Member]
Public Utilities, General Disclosures [Line Items]
Approved average annual increase	1.50%	1.10%
Nova Scotia Power Inc. [Member] \| Public Utilities Act of Nova Scotia [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Settlement Amount, Minimum Contribution Amount				10	$ 10
Nova Scotia Power Inc. [Member] \| Minimum [Member] \| Fuel Adjustment Mechanism Asset [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage					8.75%
Nova Scotia Power Inc. [Member] \| Maximum [Member] \| Fuel Adjustment Mechanism Asset [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Return on Equity, Percentage					9.25%
NSP Maritime Link Inc. [Member] \| Nova Scotia Power Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Settlement Amount, Actual Contribution Amount					$ 17
NSP Maritime Link Inc. [Member] \| Scenario, Forecast [Member] \| Nova Scotia Power Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Settlement Amount, Actual Contribution Amount			$ 53	$ 36
NSP Maritime Link Inc. [Member] \| Public Utilities Act of Nova Scotia [Member] \| Nova Scotia Power Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities refunds payable to customers					2
Public Utilities, Settlement Amount					$ 96