Organization and Accounting Policies (Narrative) (Details) $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
|
Jun. 30, 2019
USD ($)
/ $
|
Jun. 30, 2018
USD ($)
|
Jun. 30, 2019
USD ($)
/ $
|
Jun. 30, 2018
USD ($)
|
Dec. 31, 2018
USD ($)
/ $
|
|
| Organization And Accounting Policies [Line Items] | |||||
| Receivable balance, net | $ 13,828 | $ 13,828 | $ 11,907 | ||
| Exchange rate | / $ | 573.0 | ||||
| Bad debt recovery (expense) | (5) | $ (145) | 24 | $ (89) | |
| Transfers between levels | 0 | $ 0 | |||
| 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% | ||||
| Loss on foreign currency transactions | (0) | 200 | $ 200 | 100 | |
| Gabon | |||||
| Organization And Accounting Policies [Line Items] | |||||
| Receivable balance, gross, noncurrent | 8,000 | 8,000 | |||
| Receivable balance, net, noncurrent | $ 2,700 | $ 2,700 | |||
| Exchange rate | / $ | 576.6 | 576.6 | |||
| Bad debt recovery (expense) | $ (3) | $ 100 | $ 29 | $ 100 | |
| X | ||||||||||
- Definition Future Working Interest Of Carried Partner Percentage No definition available.
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- Definition Monthly Royalty Rate, Based On Production At The Published Price No definition available.
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- Definition Organization And Accounting Policies [Line Items] No definition available.
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- Definition Working Interest Of Carried Partner, Percentage No definition available.
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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy. No definition available.
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- Definition Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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