XML 58 R47.htm IDEA: XBRL DOCUMENT
v3.20.2

Crude Oil and Natural Gas Properties and Equipment (Narrative) (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 20, 2026 | Sep. 26, 2018 USD ($) | Sep. 17, 2018 USD ($) item | Feb. 29, 2020 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) item | Jun. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Reduction in VAT receivable |  |  |  |  |  | $ (695,000) | $ 718,000 |  |
Number of drilled wells required by agreement | item |  |  |  |  |  | 2 |  |  |
Number of appraisal wells required by agreement | item |  |  |  |  |  | 2 |  |  |
Impairment of proved crude oil and natural gas properties |  |  |  |  | $ 0 | $ 30,625,000 |  |  |
Property, net |  |  |  |  | 41,348,000 | 41,348,000 |  | $ 68,258,000 |
Undeveloped acreage |  |  |  |  | 21,476,000 | 21,476,000 |  | $ 23,771,000 |
Etame Marine Block [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Allocated to proved leasehold cost |  |  |  |  | 2,300,000 | 2,300,000 |  |  |
Impairment of proved crude oil and natural gas properties |  |  |  |  |  | 30,600,000 |  |  |
Property, net |  |  |  |  | 15,600,000 | 15,600,000 |  |  |
Undeveloped leasehold value |  |  |  |  | $ 11,500,000 | $ 11,500,000 |  |  |
Etame Marine Block [Member] | VAALCO Gabon S.A. [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage |  |  |  |  | 33.575% | 33.575% |  |  |
Block P Offshore Equatorial Guinea [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage |  |  |  |  | 43.00% | 43.00% |  | 31.00% |
Increase (decrease) in working interest ownership percentage |  |  |  |  |  | 12.00% |  |  |
Undeveloped acreage |  |  |  |  | $ 10,000,000.0 | $ 10,000,000.0 |  |  |
Potential payment |  |  |  |  | $ 3,100,000 | $ 3,100,000 |  |  |
Period of development |  |  |  |  |  | 25 years |  |  |
Prior Production Sharing Contract, Through September 17, 2018 [Member] | Consortium [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Entitled percent for consortium after initial royalty percentage |  |  |  |  |  | 70.00% |  |  |
Monthly royalty rate, based on production at the published price |  |  |  |  |  | 13.00% |  |  |
Prior Production Sharing Contract, Through September 17, 2018 [Member] | Government Of Gabon [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Monthly royalty rate, based on production at the published price |  |  |  |  |  | 13.00% |  |  |
Prior Production Sharing Contract, Through September 17, 2018 [Member] | Etame Marine Block [Member] | Consortium [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage |  |  |  |  | 7.50% | 7.50% |  |  |
Prior Production Sharing Contract, Through September 17, 2018 [Member] | Etame Marine Block [Member] | Government Of Gabon [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage |  |  |  |  |  |  |  |  | 7.50%
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Deferred tax assets, basis difference in fixed assets |  |  |  |  | $ 18,600,000 | $ 18,600,000 |  |  |
Deferred tax liabilities, basis difference in fixed assets |  |  |  |  | 18,600,000 | 18,600,000 |  |  |
Allocated to proved leasehold cost |  |  |  |  | 22,500,000 | 22,500,000 |  |  |
Allocated to unproved leasehold cost |  |  |  |  | 13,700,000 | 13,700,000 |  |  |
Estimated costs of technical studies |  |  |  |  |  | $ 400,000 |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Consortium [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Number of drilled wells required by agreement | item |  |  |  |  |  | 2 |  |  |
Number of appraisal wellbores required by agreement | item |  |  |  |  |  | 2 |  |  |
Number of wells drilled | item |  |  |  |  |  | 2 |  |  |
Number of wellbores drilled | item |  |  |  |  |  | 2 |  |  |
Number of technical studies required | item |  |  |  |  |  | 2 |  |  |
Estimated costs of technical studies |  |  |  |  |  | $ 1,300,000 |  |  |
Entitled percent for consortium after initial royalty percentage |  |  |  |  |  | 80.00% |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Government Of Gabon [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Monthly royalty rate, based on production at the published price |  |  |  |  |  | 13.00% |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Signing Bonus [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Contractual obligation |  |  | $ 21,800,000 |  |  |  |  |  |
Payment of signing bonus, allocated to proved and unproved property |  | $ 11,800,000 |  |  |  |  |  |  |
Reduction in VAT receivable |  | 8,400,000 |  | $ 4,200,000 |  |  |  |  |
Other accrued liabilities |  | 1,700,000 |  |  |  |  |  | $ 1,700,000 |
Allocated to unproved leasehold cost |  |  |  |  | 6,700,000 | $ 6,700,000 |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Signing Bonus [Member] | Consortium [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Contractual obligation |  |  | $ 65,000,000.0 |  |  |  |  |  |
Payment of signing bonus, allocated to proved and unproved property |  | 35,000,000.0 |  |  |  |  |  |  |
Reduction in VAT receivable |  | 25,000,000.0 |  |  |  |  |  |  |
Other accrued liabilities |  | $ 5,000,000.0 |  |  |  |  |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Tax Impact [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Allocated to unproved leasehold cost |  |  |  |  | $ 7,100,000 | $ 7,100,000 |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Etame Marine Block [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Number of exploitation areas | item |  |  | 3 |  |  |  |  |  |
Period of agreement for exploitation areas |  |  | 10 years |  |  | 10 years |  |  |
Number of contract extension periods | item |  |  | 2 |  |  |  |  |  |
Production license agreement term extended by government |  |  | 5 years |  |  |  |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Etame Marine Block [Member] | Government Of Gabon [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage |  |  |  |  | 7.50% | 7.50% |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Scenario, Forecast [Member] | Etame Marine Block [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Increase (decrease) in working interest ownership percentage | (0.80%) |  |  |  |  |  |  |  |
Production Sharing Contract, September 17, 2018 Through September 16, 2028 [Member] | Scenario, Forecast [Member] | Etame Marine Block [Member] | Government Of Gabon [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Working interest ownership, percentage | 10.00% |  |  |  |  |  |  |  |
Increase (decrease) in working interest ownership percentage | 2.50% |  |  |  |  |  |  |  |
Production Sharing Contract, After September 16, 2028 [Member] | Consortium [Member] |  |  |  |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |
Entitled percent for consortium after initial royalty percentage |  |  |  |  |  | 70.00% |  |  |

X
- Definition Entitled Percent For Consortium After Initial Royalty Percentage + References No definition available. + Details
Name: | egy_EntitledPercentForConsortiumAfterInitialRoyaltyPercentage
Namespace Prefix: | egy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Estimated Costs Of Technical Studies + References No definition available. + Details
Name: | egy_EstimatedCostsOfTechnicalStudies
Namespace Prefix: | egy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Increase (Decrease) In Value Added Tax Receivable + References No definition available. + Details
Name: | egy_IncreaseDecreaseInValueAddedTaxReceivable
Namespace Prefix: | egy_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Increase (Decrease) In Working Interest Ownership Percentage + References No definition available. + Details
Name: | egy_IncreaseDecreaseInWorkingInterestOwnershipPercentage
Namespace Prefix: | egy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Monthly Royalty Rate, Based On Production At The Published Price + References No definition available. + Details
Name: | egy_MonthlyRoyaltyRateBasedOnProductionAtPublishedPrice
Namespace Prefix: | egy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Appraisal Wellbores Drilled + References No definition available. + Details
Name: | egy_NumberOfAppraisalWellboresDrilled
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Appraisal Wellbores Required By Agreement + References No definition available. + Details
Name: | egy_NumberOfAppraisalWellboresRequiredByAgreement
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Appraisal Wells Required By Agreement + References No definition available. + Details
Name: | egy_NumberOfAppraisalWellsRequiredByAgreement
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Contract Extension Periods + References No definition available. + Details
Name: | egy_NumberOfContractExtensionPeriods
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Drilled Wells Required By Agreement + References No definition available. + Details
Name: | egy_NumberOfDrilledWellsRequiredByAgreement
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Exploitation Areas + References No definition available. + Details
Name: | egy_NumberOfExploitationAreas
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Technical Studies Required + References No definition available. + Details
Name: | egy_NumberOfTechnicalStudiesRequired
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Wells Drilled + References No definition available. + Details
Name: | egy_NumberOfWellsDrilled
Namespace Prefix: | egy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Payment Of Signing Bonus, Allocated To Proved And Unproved Property + References No definition available. + Details
Name: | egy_PaymentOfSigningBonusAllocatedToProvedAndUnprovedProperty
Namespace Prefix: | egy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Period Of Agreement For Exploitation Areas + References No definition available. + Details
Name: | egy_PeriodOfAgreementForExploitationAreas
Namespace Prefix: | egy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of development area. + References No definition available. + Details
Name: | egy_PeriodOfDevelopmentArea
Namespace Prefix: | egy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Production license agreement term extended by government. + References No definition available. + Details
Name: | egy_ProductionLicenseAgreementTermExtendedByGovernment
Namespace Prefix: | egy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Undeveloped Leasehold Value + References No definition available. + Details
Name: | egy_UndevelopedLeaseholdValue
Namespace Prefix: | egy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Working Interest Ownership, Percentage + References No definition available. + Details
Name: | egy_WorkingInterestOwnershipPercentage
Namespace Prefix: | egy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
Name: | us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -URI http://asc.fasb.org/subtopic&trid=2145654 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 + Details
Name: | us-gaap_CapitalizedCostsProvedProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -URI http://asc.fasb.org/topic&trid=2145477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 + Details
Name: | us-gaap_CapitalizedCostsUnprovedProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. + References No definition available. + Details
Name: | us-gaap_ContractualObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment. + References No definition available. + Details
Name: | us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=117330534&loc=d3e28680-109314 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 + Details
Name: | us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 35 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66906256&loc=d3e66150-109466 + Details
Name: | us-gaap_ImpairmentOfOilAndGasProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6911-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e7018-107765 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6935-107765 + Details
Name: | us-gaap_OtherAccruedLiabilitiesCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(14)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Oil and Gas properties with unproved reserves under the successful effort method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64746-109465 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61926-109447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -URI http://asc.fasb.org/topic&trid=2145477 + Details
Name: | us-gaap_UnprovedOilAndGasPropertySuccessfulEffortMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_StatementGeographicalAxis=egy_EtameMarineBlockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=egy_VaalcoGabonS.a.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=egy_BlockPOffshoreEquatorialGuineaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=egy_PriorProductionSharingContractThroughSeptember172018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=egy_VaalcoEnergyInc.AndOtherEtameMarinBlockOwnersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=egy_GovernmentOfGabonMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=egy_ProductionSharingContractSeptember172018ThroughSeptember162028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=egy_SigningBonusMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=egy_TaxImpactMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=egy_ProductionSharingContractAfterSeptember162028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |