| **Income Taxes - Narrative (Details) - USD ($) $ in Thousands**                     | 12 Months Ended |
|-------------------------------------------------------------------------------------|-----------------|
||
| **Income Tax Examination [Line Items]**                                             |            |   |   |
| Provision for income taxes                                                          | $ 10,666        | $ 4,371 | $ 7,293 |
| Benefit related to restructuring of certain subsidiary legal entities within Europe |            | 3,100 |   |
| Impairments and other non-cash charges                                              | 6,356           | 37,322 | $ 0 |
| Deferred tax assets, NOL carryforwards, federal                                     | 82,900          |   |   |
| Deferred tax assets, NOL carryforwards, state and local                             | 228,500         |   |   |
| Deferred tax assets, NOL carryforwards, foreign                                     | 25,400          |   |   |
| Capitalized research and development expenditures                                   | 7,110           | 4,342 |   |
| Deferred tax assets, valuation allowance                                            | 49,197          | $ 47,280 |   |
| Unrecognized tax benefits that would impact effective tax rate                      | 200             |   |   |
| State and Local Jurisdiction                                                        |            |   |   |
| **Income Tax Examination [Line Items]**                                             |            |   |   |
| Deferred tax assets, operating loss carryforwards, not subject to expiration        | 167,500         |   |   |
| Deferred tax assets, operating loss carryforwards, subject to expiration            | $ 61,000        |   |   |

| X                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Effective Income Tax Rate Reconciliation, Restructuring Of Foreign Entities, Amount
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| - Definition
Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.
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| - Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.
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| - Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.
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| - Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.
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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.
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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.
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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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| - Definition
The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.
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