Summary Of Significant Accounting Policies (Rollforward Analysis Of The Allowance Against Accounts Receivable Balance) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Charged to costs and expenses | $ (452) | $ (1,222) | $ (2,699) |
| Gabon [Member] | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Balance at beginning of year | (5,211) | (4,221) | (2,400) |
| Charged to costs and expenses | (452) | (1,222) | (2,699) |
| Reclassification related to Sojitz acquisition | (694) | ||
| Foreign currency gain (loss) | (676) | 232 | 878 |
| Balance at end of period | $ (7,033) | $ (5,211) | $ (4,221) |
| X | ||||||||||
- Definition Accounts Receivable Offset For Aquisitions Adjustment No definition available.
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- Definition Allowance For Bad Debts, Foreign Currency Gain No definition available.
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- 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. No definition available.
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- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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