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Income Taxes (Schedule Of Valuation Allowance Activity) (Details) - USD ($) $ in Thousands | 5 Months Ended | 7 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2015 | Aug. 14, 2015 | Dec. 31, 2016 | Dec. 31, 2014
Predecessor [Member] |  |  |  |
Valuation Allowance [Line Items] |  |  |  |
Balance at beginning of year | $ 115,449 | $ 95,721 |  | $ 20,411
(Credited) / charged to income |  | 29,363 |  | 74,157
Translation adjustment |  | (1,467) |  | (800)
Changes attributable to movement in underlying assets |  | (8,168) |  | 1,953
Balance at end of year |  | $ 115,449 |  | $ 95,721
Successor [Member] |  |  |  |
Valuation Allowance [Line Items] |  |  |  |
Balance at beginning of year |  |  | $ 165,539 |
(Credited) / charged to income | 6,780 |  | 78,469 |
Translation adjustment | (101) |  | 583 |
Changes attributable to movement in underlying assets | 43,411 |  | 250 |
Balance at end of year | $ 165,539 |  | $ 244,841 |

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