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Accumulated Other Comprehensive Income (Loss) (Schedule Of Reclassifications Of Balances Out Of Accumulated Other Comprehensive Income (Loss) Into Net Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax | $ (169,190) | $ (206,309) | $ (169,190) | $ (206,309) | $ (178,404) | $ (197,651)
Selling, general and administrative | 20,275 | 21,190 | 38,659 | 41,234 |  |
Income before income taxes | (26,451) | (18,192) | (39,166) | 8,698 |  |
Income taxes from continuing operations | (5,723) | (3,860) | (8,820) | 2,366 |  |
Net income (loss) | 21,236 | 11,196 | 30,267 | (11,126) |  |
Foreign Currency Translation |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax | (82,804) | (112,666) | (82,804) | (112,666) | (84,149) | (100,663)
Gain (Loss) on Derivative Financial Instruments |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax | 3,496 | (3,824) | 3,496 | (3,824) | 2,264 | (1,307)
Pension & Other Post-retirement Benefit Adjustment |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss), Net of Tax | (89,882) | (89,819) | (89,882) | (89,819) | $ (96,519) | $ (95,681)
Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Income before income taxes | (1,241) | 3,333 | (1,896) | 4,752 |  |
Income taxes from continuing operations | (257) | 721 | (404) | 1,027 |  |
Net income (loss) | 984 | (2,612) | 1,492 | (3,725) |  |
Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments | Aluminum Futures Contracts |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Cost of goods sold | 1,372 | (1,551) | 2,012 | (2,191) |  |
Reclassification Out Of Accumulated Other Comprehensive Income | Pension & Other Post-retirement Benefit Adjustment |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Actuarial gain (loss) and prior service costs, before taxes | (4,240) | (3,766) | (8,483) | (7,533) |  |
Income taxes from continuing operations | 922 | 835 | 1,846 | 1,671 |  |
Net income (loss) | (3,318) | (2,931) | (6,637) | (5,862) |  |
Selling, General and Administrative Expenses [Member] | Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments | Foreign Currency Forward Contracts |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Selling, general and administrative | (147) | (1,798) | (149) | (2,592) |  |
Cost of Sales [Member] | Reclassification Out Of Accumulated Other Comprehensive Income | Gain (Loss) on Derivative Financial Instruments | Foreign Currency Forward Contracts |  |  |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |
Cost of goods sold | $ 16 | $ 16 | $ 33 | $ 31 |  |

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