Income Taxes - Tax Carryforward (Details) $ in Millions	Dec. 31, 2024 CAD ($)
Tax Credit Carryforward [Line Items]
Total income tax carryforwards recognized	$ 629
Canadian
Tax Credit Carryforward [Line Items]
Non-capital loss	155
Tax credit carryforward	77
Tax carryforward, gross	232
Foreign
Tax Credit Carryforward [Line Items]
Federal and state net operating loss	315
Tax credit carryforward	82
Tax carryforward, gross	$ 397

Tax Carryforward, Amount

No definition available.

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- Definition

Tax Carryforward, Net

+ References

No definition available.

+ Details

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible loss carryforwards, classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

+ Details

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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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

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