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Narrative (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) year
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Income Taxes Receivable |  | $ 6,900,000 |  |  |
Transition tax liability |  | 5,900,000 |  |  |
Foreign earnings inclusion, Global Intangible Low-Taxed Income (GILTI) |  | 25,700,000 |  |  |
Estimate of federal limit on deductible interest expense |  | 38,000,000 |  |  |
Benefit from re-measurement of indefinite lived deferred tax liabilities |  | 2,600,000 |  |  |
Benefit from decrease in deferred tax asset valuation allowance |  | 1,500,000 |  |  |
Impact of U.S. tax reform | $ (4,100,000) |  |  |  |
Number of years in cumulative loss profit position | year |  |  |  |  | 3
Valuation allowance |  | (48,000,000) | $ (14,500,000) | $ 171,500,000 | $ 74,500,000
Income (loss) before income taxes |  | 247,700,000 | (86,500,000) | (734,000,000) |
Income from continuing operations before income taxes, domestic |  | 190,800,000 | (119,800,000) | (782,100,000) |
Accumulated other comprehensive loss, net of tax | 1,027,800,000 | 1,133,800,000 | 1,027,800,000 | 1,093,700,000 | 1,014,500,000
Transition tax expense |  | 5,900,000 | 0 |  |
Impact of U.S. tax reform |  | (5,900,000) | 4,100,000 | 0 |
Foreign income taxable due to legislative changes |  |  | 100,000,000 |  |
Transition tax for accumulated foreign earnings, liability | 35,000,000 | 34,100,000 | 35,000,000 |  |
Mandatory repatriation of foreign earnings, income |  | 97,500,000 |  |  |
Total deferred income tax assets | 468,900,000 | 478,800,000 | 468,900,000 |  |
Payment of transition tax for accumulated foreign earnings |  | 500,000 |  |  |
Net operating loss tax carryovers | 336,100,000 | 307,500,000 | 336,100,000 |  |
Income tax refunds received |  | 1,600,000 | 7,100,000 | 10,500,000 |
Deferred taxes for foreign withholding taxes |  | 3,200,000 |  |  |
Unrecognized tax benefits classified within deferred taxes as a reduction of net operating loss carryforwards | 11,700,000 | 12,100,000 | 11,700,000 |  |
Unrecognized tax benefits that would impact effective tax rate |  | 3,000,000 |  |  |
Unrecognized tax benefits that will be recognized within 12 months of year end |  | 1,000,000 |  |  |
Tax Cuts and Jobs Act Of 2017, Transition Tax for Accumulated Foreign Earnings, Deferred Tax Asset Adjustment |  | (1,200,000) |  |  |
Federal and State Deferred Tax Assets |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Valuation allowance |  | (46,300,000) |  | 165,800,000 | 68,400,000
Accumulated Deferred Tax Asset Valuation Allowance |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Accumulated other comprehensive loss, net of tax | 28,800,000 | 49,300,000 | 28,800,000 | 45,600,000 | $ 0
State [Member] |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Tax credit carryforwards |  | 12,000,000 |  |  |
Federal |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Income tax refunds received |  |  | 3,200,000 | $ 7,300,000 |
Tax Cuts and Jobs Act, Transition Tax Liability |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Tax credit carryforwards |  | 28,200,000 |  |  |
Total deferred income tax assets | 468,900,000 |  | 468,900,000 |  |
Net operating loss tax carryovers | 355,900,000 |  | 355,900,000 |  |
Tax Cuts and Jobs Act, Transition Tax Liability | Scenario, Adjustment |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Total deferred income tax assets | 0 |  | 0 |  |
Net operating loss tax carryovers | $ 19,800,000 |  | $ 19,800,000 |  |
Tax Cuts and Jobs Act, NOL preserved [Member] |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |
Net operating loss tax carryovers |  | $ 97,500,000 |  |  |

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