| **Income and other Taxes (Narrative) (Details) - USD ($) $ in Thousands** | 3 Months Ended | 12 Months Ended |
|---------------------------------------------------------------------------|----------------|-----------------|
||
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Income tax benefit                                                        | $ 339          | $ (456)         | $ 396 | $ 1,912 | $ 23,171 | $ 732 | $ (433) | $ 1,080 | $ 2,191 | $ 24,550 | $ 3,393 |
| Alternative minimum tax                                                   |           |            |   |   |   |   |   |   | 600 |   |   |
| Deferred income tax expense benefit from discontinued operations          |           |            |   |   |   |   |   |   | 24,100 |   |   |
| Discontinued operations, tax effect                                       |           |            |   |   |   |   |   |   | $ (26,500) | $ (500) | $ (3,500) |
| Effective tax rate                                                        |           |            |   |   |   |   |   |   | (49.10%) | (119.90%) | (37.90%) |
| Decrease in unrecognized tax benefits                                     |           |            |   |   |   |   |   |   | $ 200 |   |   |
| Income tax penalties and interest accrued                                 | 300            |            |   |   | $ 400 |   |   |   | 300 | $ 400 |   |
| Operating loss carryforward portion subject limitation                    | 247,300        |            |   |   |   |   |   |   | 247,300 |   |   |
| Operating loss carryforward portion not subject to limitation             | 187,100        |            |   |   |   |   |   |   | 187,100 |   |   |
| Foreign Income And Research And Development Credit [Member]               |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Tax credit carryforward                                                   | 3,000          |            |   |   |   |   |   |   | 3,000 |   |   |
| Internal Revenue Service (IRS) [Member]                                   |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Operating loss carryforwards                                              | 434,400        |            |   |   |   |   |   |   | 434,400 |   |   |
| Foreign Tax Authority [Member]                                            |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Operating loss carryforwards                                              | 500            |            |   |   |   |   |   |   | 500 |   |   |
| State and Local Jurisdiction [Member]                                     |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Operating loss carryforwards                                              | $ 243,000      |            |   |   |   |   |   |   | 243,000 |   |   |
| Continuing Operations [Member]                                            |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Decrease in unrecognized tax benefits                                     |           |            |   |   |   |   |   |   | 100 |   |   |
| Discontinued Operations [Member]                                          |           |            |   |   |   |   |   |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                             |           |            |   |   |   |   |   |   |   |   |   |
| Decrease in unrecognized tax benefits                                     |           |            |   |   |   |   |   |   | 100 |   |   |
| Income tax credits and adjustments                                        |           |            |   |   |   |   |   |   | $ 200 | $ 800 | $ 1,800 |

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| - Definition
Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.
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| - Definition
Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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| - Definition
A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.
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| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
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| - Definition
The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
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| - Definition
Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.
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The net amount of all increases and decreases in unrecognized tax benefits for the period.
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