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Transactions with Related Parties - Additional Information (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Related Party Transaction [Line Items] |  |  |
Amounts of sales by Imperial | $ 8,569 | $ 6,383 | $ 4,110
Financing costs | 98 | 89 | $ 60
Long-Term Loans |  |  |
Related Party Transaction [Line Items] |  |  |
Outstanding loans from an affiliate | 4,447 | 4,447 |
Short-Term Loans |  |  |
Related Party Transaction [Line Items] |  |  |
Outstanding loans from an affiliate | 111 | 75 |
Exxon Mobil |  |  |
Related Party Transaction [Line Items] |  |  |
Amounts of purchases by Imperial | 3,245 | 4,036 |
Amounts of sales by Imperial | 8,552 | 6,364 |
Financing costs | $ 96 | $ 87 |

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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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