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Income Taxes (Net Operating and Capital Loss Carryforwards) (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Net deferred tax assets |  |
Total net deferred tax assets | $ 88.1 | $ 40.4
Tax credit carryforwards, foreign | 3.8 |
Alternative minimum tax credit carryforwards, not subject to expiration | 0.4 |
Operating and Capital Loss Carryforward |  |
Net deferred tax assets |  |
Operating loss carryforwards | 598.9 |
Gross deferred tax asset | 129.7 |
Valuation allowance | (104.9) |
Total net deferred tax assets | 24.8 |
Operating and Capital Loss Carryforward | United States |  |
Net deferred tax assets |  |
Operating loss carryforwards | 420.1 |
Gross deferred tax asset | 88.0 |
Valuation allowance | (63.5) |
Total net deferred tax assets | 24.5 |
Operating and Capital Loss Carryforward | Luxembourg |  |
Net deferred tax assets |  |
Operating loss carryforwards | 86.5 |
Gross deferred tax asset | 21.6 |
Valuation allowance | (21.5) |
Total net deferred tax assets | 0.1 |
Operating and Capital Loss Carryforward | United Kingdom |  |
Net deferred tax assets |  |
Operating loss carryforwards | 18.7 |
Gross deferred tax asset | 3.2 |
Valuation allowance | (3.0) |
Total net deferred tax assets | 0.2 |
Operating and Capital Loss Carryforward | Israel |  |
Net deferred tax assets |  |
Operating loss carryforwards | 73.6 |
Gross deferred tax asset | 16.9 |
Valuation allowance | (16.9) |
Total net deferred tax assets | 0.0 |
2019-2023 | Operating and Capital Loss Carryforward |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.1 |
2019-2023 | Operating and Capital Loss Carryforward | United States |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.1 |
2019-2023 | Operating and Capital Loss Carryforward | Luxembourg |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2019-2023 | Operating and Capital Loss Carryforward | United Kingdom |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2019-2023 | Operating and Capital Loss Carryforward | Israel |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2024-2028 | Operating and Capital Loss Carryforward |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2024-2028 | Operating and Capital Loss Carryforward | United States |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2024-2028 | Operating and Capital Loss Carryforward | Luxembourg |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2024-2028 | Operating and Capital Loss Carryforward | United Kingdom |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2024-2028 | Operating and Capital Loss Carryforward | Israel |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2029-2038 | Operating and Capital Loss Carryforward |  |
Net deferred tax assets |  |
Operating loss carryforwards | 360.6 |
2029-2038 | Operating and Capital Loss Carryforward | United States |  |
Net deferred tax assets |  |
Operating loss carryforwards | 302.6 |
2029-2038 | Operating and Capital Loss Carryforward | Luxembourg |  |
Net deferred tax assets |  |
Operating loss carryforwards | 58.0 |
2029-2038 | Operating and Capital Loss Carryforward | United Kingdom |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
2029-2038 | Operating and Capital Loss Carryforward | Israel |  |
Net deferred tax assets |  |
Operating loss carryforwards | 0.0 |
No expiration date | Operating and Capital Loss Carryforward |  |
Net deferred tax assets |  |
Operating loss carryforwards | 238.2 |
No expiration date | Operating and Capital Loss Carryforward | United States |  |
Net deferred tax assets |  |
Operating loss carryforwards | 117.4 |
No expiration date | Operating and Capital Loss Carryforward | Luxembourg |  |
Net deferred tax assets |  |
Operating loss carryforwards | 28.5 |
No expiration date | Operating and Capital Loss Carryforward | United Kingdom |  |
Net deferred tax assets |  |
Operating loss carryforwards | 18.7 |
No expiration date | Operating and Capital Loss Carryforward | Israel |  |
Net deferred tax assets |  |
Operating loss carryforwards | $ 73.6 |

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