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Related Paty Transactions (Narrative) (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
NSPML | Regulated
Related Party Transaction [Line Items]
Purchases from Related Party	$ 139	$ 107
M&NP | Non-Regulated
Related Party Transaction [Line Items]
Purchases from Related Party	$ 18	$ 63

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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.

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No definition available.

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- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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- Details

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- Details

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