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Final repayment of principal amount.

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Long-term debt, loans, capital lease obligations, perpetual consolidated debenture stock, current and non-current.

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Payments For Hedge, Operating Activities

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Amount of assets pledged to secure a debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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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.

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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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.

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No definition available.

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- Definition

Gross amount of debt extinguished.

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No definition available.

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- Definition

Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt - Long-term Debt - Narrative (Details) $ in Millions						3 Months Ended	12 Months Ended
Debt - Long-term Debt - Narrative (Details) $ in Millions	Dec. 02, 2021 CAD ($)	Dec. 02, 2021 USD ($)	Dec. 02, 2021 CAD ($)	Dec. 02, 2021 USD ($)	Nov. 24, 2021 CAD ($)	Dec. 31, 2022 CAD ($)	Dec. 31, 2022 CAD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 CAD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 02, 2021 USD ($)
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 19,771	$ 19,771		$ 20,264
Annual maturities and principal repayments in 2022						1,504	1,504
Annual maturities and principal repayments in 2023						2,118	2,118
Annual maturities and principal repayments in 2024						948	948
Annual maturities and principal repayments in 2025						1,693	1,693
Annual maturities and principal repayments in 2026						0	0
Long-Term Debt, Maturity, after Year Five						13,520	13,520
Proceeds from issuance of long-term debt			$ 8,600	$ 6,700,000,000	$ 2,200	10,700
Payment for settlement of derivatives									226
Net book value						102	102		166
Bond locks
Debt Instrument [Line Items]
Derivative notional amount settled	$ 600
Forward starting swaps
Debt Instrument [Line Items]
Derivative notional amount settled		$ 2,400,000,000
4.500% 10-year Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 0	0		317
Extinguishment of debt, amount							$ 313	$ 250,000,000
Interest rate						4.50%	4.50%				4.50%
Debt term							10 years	10 years
2.450% 10-year Notes and 3.000% 20-year Notes
Debt Instrument [Line Items]
Redemption price percentage							101.00%	101.00%
2.450% 10-year Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 1,896	$ 1,896		1,774
Interest rate	2.45%		2.45%			2.45%	2.45%				2.45%		2.45%
Proceeds from issuance of long-term debt			$ 1,780	1,390,000,000
Debt face amount	$ 1,400		$ 1,400										$ 1,400,000,000
Debt term							10 years	10 years
3.000% 20-year Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 1,348	$ 1,348		$ 1,261
Interest rate	3.00%		3.00%			3.00%	3.00%				3.00%		3.00%
Proceeds from issuance of long-term debt			$ 1,260	$ 990,000,000
Debt face amount	$ 1,000		$ 1,000										$ 1,000,000,000.0
Debt term							20 years	20 years
9.450% 30-year Debentures
Debt Instrument [Line Items]
Extinguishment of debt, amount										$ 250,000,000
Interest rate									9.45%			9.45%
Debt term									30 years	30 years
Repayments of debt									$ 312	$ 250,000,000
2.050% 10-year Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 676	$ 676		633
Interest rate						2.05%	2.05%				2.05%
Debt term							10 years	10 years
3.050% 30-year Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 298	$ 298		298
Interest rate						3.05%	3.05%				3.05%
Debt term							30 years	30 years
5.41% Senior Secured Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 76	$ 76		80
Interest rate						5.41%	5.41%				5.41%
Value of locomotive units used as collateral						$ 89	$ 89
Final repayment of principal amount								$ 44,000,000
6.91% Secured Equipment Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 40	$ 40		58
Interest rate						6.91%	6.91%				6.91%
Value of locomotive units used as collateral						$ 31	$ 31
Final repayment of principal amount							11
5.100% 10-year Medium Term Notes
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current						$ 0	0		$ 125
Extinguishment of debt, amount							$ 125
Interest rate						5.10%	5.10%				5.10%
Debt term							10 years	10 years
6.99 Finance Lease
Debt Instrument [Line Items]
Extinguishment of debt, amount							$ 97	$ 76,000,000
Interest rate						6.99%	6.99%				6.99%
U.S dollar-denominated
Debt Instrument [Line Items]
Long-term debt and finance lease obligation, Current and non-current											$ 12,161,000,000	$ 13,265,000,000