Excess fuel recvoery payable to customers.

No definition available.

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- Definition

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499958&loc=d3e44213-110381

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- Definition

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

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

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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.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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Regulatory Assets and Liabilities (ROE of NSPI) (Details) - CAD ($) $ in Millions		12 Months Ended
	Jul. 19, 2016	Dec. 31, 2017	Dec. 31, 2016
Public Utilities, General Disclosures [Line Items]
Public Utilities refunds payable to customers		$ 17
Phase-in Plan, Amount of Costs Deferred for Rate-making Purposes		53
Regulatory Liabilities		2,468	$ 1,639
Regulatory Assets		$ 1,376	1,322
Fuel Adjustment Mechanism Liability Deferral Account [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities refunds payable to customers			$ 36
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	1.10%
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%