Revenue - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Remaining performance obligations, transaction price	$ 140	$ 135
Remaining performance obligations, expected year of revenue recognition	2042
Asset Management Agreement [Member] \| Emera Energy Services Inc [Member]
Disaggregation of Revenue [Line Items]
Remaining performance obligations, transaction price	$ 11
Remaining performance obligations, expected year of revenue recognition	2025

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.

No definition available.

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045

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- Definition

Year in which remaining performance obligation is expected to be recognized, in YYYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045

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