Revenue Contract Balances (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Changes in Contract Liabilities [Roll Forward]
Increases due to amounts billed to customers	$ 0	$ 2
Changes in transaction price	11	0
Performance obligations satisfied	(1)	(2)
Current contract liabilities	19	1
Non-current contract liabilities	13	14
IFRS 16
Changes in Contract Liabilities [Roll Forward]
Contract liabilities at beginning of period	15	15
Amounts transferred to revenue included in opening balance	(1)	(1)
Consideration received	8	1
Contract liabilities at end of period	$ 32	$ 15

The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Subsidiaries [member]]

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The amount of an entity’s obligation to transfer goods or services to a customer for which the entity has received consideration (or the amount is due) from the customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The amount of current contract liabilities. [Refer: Contract liabilities]

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- Definition

The increase (decrease) in contract liabilities resulting from cumulative catch-up adjustments to revenue arising from a change in an estimate of the transaction price. The transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties (for example, some sales taxes). [Refer: Increase (decrease) through cumulative catch-up adjustments to revenue, contract liabilities]

+ References

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The amount of non-current contract liabilities. [Refer: Contract liabilities]

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- Definition

The amount of revenue from performance obligations satisfied (or partially satisfied) in previous periods. [Refer: Performance obligations [member]; Revenue from contracts with customers]

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- Definition

The amount of revenue that was included in the contract liability balance at the beginning of the period. [Refer: Contract liabilities; Revenue from contracts with customers]

+ References

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Changes in Contract Liabilities [Roll Forward]

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- Definition

Consideration paid

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