Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

Name:	us-gaap_DerivativeNonmonetaryNotionalAmount
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Balance Type:	na
Period Type:	instant

- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeSwapTypeAverageFixedPrice
Namespace Prefix:	us-gaap_
Data Type:	srt-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=egy_CommodityContractJune2018ThroughJune2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=egy_CommodityContractJuly19ThroughJune2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
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Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=egy_CommodityContractFebruary2021ThroughJanuary2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Derivatives and Fair Value (Narrative) (Details)	Jan. 22, 2021 $ / bbl bbl	May 06, 2019 $ / bbl bbl	Jun. 30, 2018 bbl $ / bbl
Commodity Contract, June 2018 Through June 2019 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, average price per barrel \| $ / bbl			74.00
Derivative, nonmonetary notional amount \| bbl			400,000
Commodity Contract, July 19 Through June 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, average price per barrel \| $ / bbl		66.70
Barrels \| bbl		500,000
Subsequent Event [Member] \| Commodity Contract, February 2021 Through January 2022 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, average price per barrel \| $ / bbl	53.10
Barrels \| bbl	709,262