Asset Transactions and Impairments - White Rose assets (Details) - White Rose $ in Millions	3 Months Ended
Jun. 30, 2022 CAD ($) bbl / d $ / bbl	Mar. 31, 2022
Asset Transactions and Impairments
Additional interest acquired (as a percent)	12.50%
Ownership interest (as percent)	39.00%	26.00%
Cash received in transaction to acquire additional ownership interest	$ 38
Tax effect of transaction to acquire additional ownership interest	12
Reversal of impairment loss, net of tax	542
Tax effect of the reversal of impairment loss	173
Company's share of future capital expenditures	$ 1,500
Impairment testing assumption, risk-adjusted discount rate, after tax	9.00%
Forecast for the first half of 2026
Asset Transactions and Impairments
Impairment testing assumption, share of barrels per day of crude oil produced \| bbl / d	9,800
Brent crude oil \| Forecast for 2023
Asset Transactions and Impairments
Impairment testing assumption, price per barrel \| $ / bbl	85.00
Brent crude oil \| Forecast for 2024
Asset Transactions and Impairments
Impairment testing assumption, price per barrel \| $ / bbl	68.00
Brent crude oil \| Forecast for 2025
Asset Transactions and Impairments
Impairment testing assumption, price per barrel \| $ / bbl	69.00
Brent crude oil \| Forecast for 2026 to 2038
Asset Transactions and Impairments
Impairment testing assumption, price per barrel escalation percentage	2.00%

The discount rate applied to cash flow projections for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

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The amount of the Company's share of expected future capital expenditures in a joint operation.

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The amount recognised as an increase of the carrying amount of an asset or cash-generating unit to its recoverable amount when an impairment loss had been previously recognised, net of tax effect.

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The tax effect to acquire additional ownership interest.

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