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v3.20.1

Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands, in Billions |  |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
May 06, 2019 $ / bbl bbl | Sep. 26, 2018 USD ($) | Sep. 17, 2018 USD ($) | Sep. 17, 2018 XAF ( ) | Dec. 31, 2019 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2019 USD ($) bbl | Dec. 31, 2018 USD ($) $ / bbl | Dec. 31, 2017 USD ($) | Dec. 31, 2019 XAF ( ) / $
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Reduction in VAT receivable |  |  |  |  |  |  | $ 275 | $ (777) | $ (3,025) |
Exchange rate | / $ |  |  |  |  |  |  |  |  |  | 585.7
Bad debt recovery (expense) |  |  |  |  |  |  | 341 | 77 | (452) |
Inventory adjustment |  |  |  |  |  |  | 0 |  | 0 |
Interest Costs Capitalized |  |  |  |  |  |  | 0 | 0 | 0 |
Asset retirement obligation, revision of estimate |  |  |  |  | $ (400) |  | $ (379) | $ (6,527) | 703 |
Monthly royalty rate, based on production at the published price |  |  |  |  |  |  | 13.00% |  |  |
Working interest of carried partner, percentage |  |  |  |  |  |  | 7.50% |  |  |
Future working interest of carried partner percentage |  |  |  |  |  |  | 10.00% |  |  |
Derivative cap price | $ / bbl |  |  |  |  |  |  |  | 74.00 |  |
Derivative floor price | $ / bbl |  |  |  |  |  |  |  | 74.00 |  |
Gain (loss) on foreign currency transactions |  |  |  |  |  |  | $ (200) | $ (100) | 500 |
Barrels | bbl |  |  |  |  |  |  | 274,870 |  |  |
Cash received to settle derivatives |  |  |  |  |  |  | $ 2,400 | 700 | 200 |
Restatement Adjustment [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Accrued liabilities |  |  |  |  |  |  |  |  | (2,600) |
Office Equipment [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  | 5 years |  |  |
Leasehold Improvements [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  | 5 years |  |  |
Leasehold Improvements [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated useful life |  |  |  |  |  |  | 7 years |  |  |
Gabon [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Receivable balance, gross | |  |  |  |  |  |  |  |  |  | 5.4
Receivable balance, net, noncurrent | |  |  |  |  |  |  |  |  |  | 1.8
Reduction in VAT receivable, gross amount |  | $ 25,000 |  | 14.1 |  |  |  |  |  |
Reduction in VAT receivable |  | $ 8,400 | $ 4,200 | 4.7 |  |  |  |  |  |
Bad debt recovery (expense) |  |  |  |  |  |  | $ 300 | 100 | $ (400) |
Inventory adjustment |  |  |  |  |  |  |  | 400 |  |
Asset retirement obligation, revision of estimate |  |  |  |  |  | $ 400 |  |  |  |
Etame Field [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Asset retirement obligation, revision of estimate |  |  |  |  |  | $ 600 |  | $ (6,500) |  |
Commodity Contract, July 19 Through June 2020 [Member] |  |  |  |  |  |  |  |  |  |
Organization And Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative, average price per barrel | $ / bbl | 66.70 |  |  |  |  |  |  |  |  |
Barrels | bbl | 500,000 |  |  |  |  |  |  |  |  |

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