The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of provision for onerous contracts. An onerous contract is a contract in which the unavoidable costs of meeting the obligation under the contract exceed the economic benefits expected to be received under it. [Refer: Other provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

The amount of operating income (expense) that the entity does not separately disclose in the same statement or note.

+ References

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Analysis of income and expenses [Line Items]

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Gain (loss) on energy supply agreement

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Gains (Losses) on Contract Agreement

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Gains (Losses) on Contract Agreement, Net

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Net Other Operating Expense (Income) (Details) $ in Millions, $ in Millions		12 Months Ended
	Jul. 20, 2018 CAD ($)	Dec. 31, 2021 CAD ($)	Dec. 31, 2020 CAD ($)	Dec. 31, 2019 CAD ($)	Dec. 31, 2021 USD ($)
Analysis of income and expenses [Line Items]
Alberta Off-Coal Agreement	$ (40)	$ (40)	$ (40)	$ (40)
Alberta off-coal agreement, annual cash payments, net		37
Other operating income (expense)		8	(11)	(49)
Onerous contract provisions		14	29	$ 0
Onerous contracts provision			$ 29
Sundance Unit 5
Analysis of income and expenses [Line Items]
Net deferred tax assets		$ 10			$ 8