Post Retirement Benefit Plans - Summary of Healthcare Cost Trend Rates on Gross Eligible Charges (Detail) - Other Postretirement Benefits Plan	12 Months Ended
Oct. 31, 2018
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Current trend rate	6.60%
Ultimate trend rate	4.90%
South Africa
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Year ultimate trend rate reached	2020
United States
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Year ultimate trend rate reached	2026

Pension plans, postretirement and other employee benefits.

No definition available.

Name:	gef_PensionPlansPostretirementAndOtherEmployeeBenefitsLineItems
Namespace Prefix:	gef_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate
Namespace Prefix:	us-gaap_
Data Type:	us-types:gYearListItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=country_ZA
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: