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Income Taxes (Net Operating and Capital Loss Carryforwards) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Net deferred tax assets |  |
Total net deferred income tax assets | $ 27.5 | $ 32.7
Alternative minimum tax credit carryforwards, not subject to expiration | 1.3 |
Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 3.1 |
Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 471.4 |
Net deferred tax assets |  |
Gross deferred tax asset | 106.9 |
Valuation allowance | (106.9) |
Total net deferred income tax assets | 0.0 |
Operating and Capital Loss Carryforward | Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 332.3 |
Net deferred tax assets |  |
Gross deferred tax asset | 73.0 |
Valuation allowance | (73.0) |
Total net deferred income tax assets | 0.0 |
Operating and Capital Loss Carryforward | Luxembourg |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 77.7 |
Net deferred tax assets |  |
Gross deferred tax asset | 20.2 |
Valuation allowance | (20.2) |
Total net deferred income tax assets | 0.0 |
Operating and Capital Loss Carryforward | United Kingdom |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 6.7 |
Net deferred tax assets |  |
Gross deferred tax asset | 1.1 |
Valuation allowance | (1.1) |
Total net deferred income tax assets | 0.0 |
Operating and Capital Loss Carryforward | Israel |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 54.7 |
Net deferred tax assets |  |
Gross deferred tax asset | 12.6 |
Valuation allowance | (12.6) |
Total net deferred income tax assets | 0.0 |
2018-2022 | Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.3 |
2018-2022 | Operating and Capital Loss Carryforward | Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.3 |
2018-2022 | Operating and Capital Loss Carryforward | Luxembourg |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2018-2022 | Operating and Capital Loss Carryforward | United Kingdom |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2018-2022 | Operating and Capital Loss Carryforward | Israel |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2023-2027 | Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2023-2027 | Operating and Capital Loss Carryforward | Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2023-2027 | Operating and Capital Loss Carryforward | Luxembourg |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2023-2027 | Operating and Capital Loss Carryforward | United Kingdom |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2023-2027 | Operating and Capital Loss Carryforward | Israel |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2028-2037 | Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 378.4 |
2028-2037 | Operating and Capital Loss Carryforward | Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 332.0 |
2028-2037 | Operating and Capital Loss Carryforward | Luxembourg |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 46.4 |
2028-2037 | Operating and Capital Loss Carryforward | United Kingdom |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
2028-2037 | Operating and Capital Loss Carryforward | Israel |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
No expiration date | Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 92.7 |
No expiration date | Operating and Capital Loss Carryforward | Unites States |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 0.0 |
No expiration date | Operating and Capital Loss Carryforward | Luxembourg |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 31.3 |
No expiration date | Operating and Capital Loss Carryforward | United Kingdom |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 6.7 |
No expiration date | Operating and Capital Loss Carryforward | Israel |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | 54.7 |
2030 | Operating and Capital Loss Carryforward |  |
Summary of net operating loss and capital loss carryforwards, the expiration dates and the deferred tax assets thereon |  |
Operating loss carryforwards | $ (6.7) |

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