Amount of short-term and long-term debt and lease obligation.

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Weighted average interest rate of debt outstanding.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Debt and Interest Rate Derivatives - Components of Debt (Detail) $ in Millions, $ in Millions	Mar. 31, 2020 CAD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 CAD ($)	Dec. 31, 2019 USD ($)
Debt
Debt		$ 13,452		$ 13,498
Debt issuance costs, discounts and other		(81)		(85)
Current portion of long-term debt		387		218
Long-term debt, less current portion		13,065		13,280
Senior Notes, Aggregate [Member]
Debt
Debt		$ 9,965		$ 9,965
Weighted average interest rate	3.90%	3.90%	3.90%	3.90%
Canadian Senior Notes [Member]
Debt
Debt	$ 500	$ 355	$ 500	$ 385
Interest rate (as a percent)	2.60%	2.60%	2.60%	2.60%
Tax Exempt Bonds [Member]
Debt
Debt		$ 2,523		$ 2,523
Current portion of long-term debt		$ 130
Weighted average interest rate	2.70%	2.70%	2.30%	2.30%
Financing leases and other [Member]
Debt
Debt		$ 690		$ 710
Current portion of long-term debt		$ 237
Weighted average interest rate	4.70%	4.70%
Minimum [Member] \| Senior Notes, Aggregate [Member]
Debt
Interest rate (as a percent)	2.40%	2.40%	2.40%	2.40%
Minimum [Member] \| Tax Exempt Bonds [Member]
Debt
Interest rate (as a percent)	1.10%	1.10%
Maximum [Member] \| Senior Notes, Aggregate [Member]
Debt
Interest rate (as a percent)	7.75%	7.75%	7.75%	7.75%
Maximum [Member] \| Tax Exempt Bonds [Member]
Debt
Interest rate (as a percent)	5.50%	5.50%