XML 45 R89.htm IDEA: XBRL DOCUMENT v2.4.1.9
Long Term Debt - Additional Information (Detail) (CAD)
In Millions, unless otherwise specified
1 Months Ended 3 Months Ended
Feb. 11, 2015
Sep. 30, 2014
Dec. 31, 2014
Jan. 31, 2014
Dec. 31, 2013
Subsequent Event          
Line of Credit Facility [Line Items]          
Drawing from existing facility 490us-gaap_ProceedsFromLinesOfCredit
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
       
Revolving demand loan          
Line of Credit Facility [Line Items]          
Line of Credit maximum borrowing capacity   500us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
     
Debt instrument, maturity date   Aug. 31, 2016      
Revolving demand loan | Exxon Mobil          
Line of Credit Facility [Line Items]          
Line of Credit maximum borrowing capacity     75us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_LineOfCreditFacilityAxis
= imo_ExxonMobilCorporationMember
   
Floating Rate Loan Facility | Exxon Mobil          
Line of Credit Facility [Line Items]          
Line of Credit maximum borrowing capacity       6,250us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= imo_FloatingRateLoansMember
/ us-gaap_LineOfCreditFacilityAxis
= imo_ExxonMobilCorporationMember
5,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= imo_FloatingRateLoansMember
/ us-gaap_LineOfCreditFacilityAxis
= imo_ExxonMobilCorporationMember