Derivative gain loss amortization period in number of years.

No definition available.

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- Definition

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580

+ Details

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Period Type:	instant

- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

+ Details

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Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

+ Details

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

+ Details

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Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Derivatives Instruments (Derivative Cash Flow Hedges Recorded in Income and AOCI and Notional Volumes of Outstanding Derivatives Designated as Cash Flow Hedges) (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	May 26, 2021
FX forwards
Cash Flow Hedges
Notional volumes of outstanding derivatives designated as cash flow hedges that are expected to settle	$ 448
Cash flow hedges \| Interest Expense [Member]
Cash Flow Hedges
Unrealized gains reclassified into interest expense	2	$ 1
Cash flow hedges \| Treasury Lock [Member]
Cash Flow Hedges
Total unrealized gain (loss) in AOCI - effective portion, net of tax	16	$ 18	$ 19
Unrealized gains currently in AOCI to be reclassified into net income within the next twelve months	$ 2
Derivative gain loss amortization period	10 years