XML 44 R48.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Income Taxes (Parenthetical) (Detail)	Jun. 28, 2019	Nov. 02, 2017
Alberta government [Member]
Schedule Of Income Tax [Line Items]
Increase/Decrease in the provincial tax rate	(4.00%)
Alberta government [Member] | Minimum
Schedule Of Income Tax [Line Items]
Provincial tax rate	8.00%
Alberta government [Member] | Maximum
Schedule Of Income Tax [Line Items]
Provincial tax rate	12.00%
British columbia government [Member]
Schedule Of Income Tax [Line Items]
Increase/Decrease in the provincial tax rate		1.00%
British columbia government [Member] | Minimum
Schedule Of Income Tax [Line Items]
Provincial tax rate		11.00%
British columbia government [Member] | Maximum
Schedule Of Income Tax [Line Items]
Provincial tax rate		12.00%

X

- Definition

Effective income tax rate reconciliation increase decrease in provincial tax rate.

+ References

No definition available.

+ Details

Name:	imo_EffectiveIncomeTaxRateReconciliationIncreaseDecreaseInProvincialTaxRate
Namespace Prefix:	imo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Effective income tax rate reconciliation provincial tax rate.

+ References

No definition available.

+ Details

Name:	imo_EffectiveIncomeTaxRateReconciliationProvincialTaxRate
Namespace Prefix:	imo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Schedule Of Income Tax [Line Items]

+ References

No definition available.

+ Details

Name:	imo_ScheduleOfIncomeTaxLineItems
Namespace Prefix:	imo_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=imo_AlbertaGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=imo_BritishColumbiaGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: