Extinguishment of Debt, Accrued Interest

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events (Details) - CAD ($) $ in Millions		12 Months Ended
Subsequent Events (Details) - CAD ($) $ in Millions	Jan. 18, 2021	Dec. 31, 2020	Jan. 26, 2021
Subsequent events
Subsequent event, description		On January 26, 2021, the Board of Directors of the Company approved a new NCIB, which allows for the repurchase of up to 14 million common shares between February 1, 2021 and January 31, 2022. The Company expects to resume its share repurchases in the first quarter of 2021 under the new NCIB.Notes and debenturesOn January 18, 2021, as a result of lower prevailing interest rates and pursuant to an early repayment option within the Company’s fixed rate debt agreements, the Company repaid in full the seven-year 2.75% Notes due February 18, 2021. The payment consisted of $250 million of principal plus $3 million of accrued interest.
Canadian National series, 2.75% 7-year notes [Member]
Subsequent events
Term of Issuance		7 years
Subsequent Event [Member]
Subsequent events
Repayment of debt	$ 250
Accrued interest	$ 3
Subsequent Event [Member] \| February 1, 2021 - January 31, 2022 [Member]
Subsequent events
NCIB February 1, 2021 - January 31, 2022 (in shares)			14,000,000
Subsequent Event [Member] \| Canadian National series, 2.75% 7-year notes [Member]
Subsequent events
Term of Issuance	7 years
Interest rate	2.75%