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Narrative (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2019 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2015 year | Dec. 31, 2016 USD ($)
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |
Income tax penalties and interest accrued | $ 2.7 | $ 2.7 | $ 2.7 |  |  |
Foreign earnings inclusion, Global Intangible Low-Taxed Income (GILTI) |  | 16.8 | 25.7 |  |  |
Repatriation of foreign earnings (GILTI starting in 2018) |  | 3.5 | 5.4 | $ 14.2 |  |
Estimate of federal limit on deductible interest expense |  | 24.0 |  |  |  |
Restructuring |  | 4.2 | 0.0 | 0.0 |  |
Benefit from re-measurement of indefinite lived deferred tax liabilities |  |  |  | 2.6 |  |
Benefit from decrease in deferred tax asset valuation allowance |  |  |  | 1.5 |  |
Number of years in cumulative loss profit position | year |  |  |  |  | 3 |
Valuation allowance |  | (90.1) | (48.0) | (14.5) |  |
Income (loss) before income taxes |  | 241.6 | 247.7 | (86.5) |  |
Income from continuing operations before income taxes, domestic |  | 190.2 | 190.8 | (119.8) |  |
Valuation allowance decrease due to change in judgment on the realizability of deferred tax assets | (41.9) | (45.1) |  |  |  |
Accumulated other comprehensive loss, net of tax | 1,201.7 | 1,201.7 | 1,133.8 | 1,027.8 |  | $ 1,093.7
Tax expense for the recognition of a stranded deferred tax balance arising from deferred tax valuation allowances that was associated with a cash flow hedge portfolio | 6.0 |  |  |  |  |
Transition tax expense |  |  | 5.9 |  |  |
Impact of U.S. tax reform |  | 0.0 | 5.9 | (4.1) |  |
Total deferred income tax assets | 537.9 | 537.9 | 478.8 |  |  |
Net operating loss tax carryovers | 264.4 | 264.4 | 307.5 |  |  |
Income tax refunds received |  | 9.2 | 1.6 | 7.1 |  |
Deferred taxes for foreign withholding taxes | 3.5 | 3.5 |  |  |  |
Unrecognized tax benefits classified within deferred taxes as a reduction of net operating loss carryforwards | 11.5 | 11.5 | 12.1 | 11.7 |  |
Unrecognized tax benefits that would impact effective tax rate | 3.0 | 3.0 |  |  |  |
Unrecognized tax benefits that will be recognized within 12 months of year end | 2.0 | 2.0 |  |  |  |
Federal and State Deferred Tax Assets |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |
Valuation allowance |  |  | (46.3) |  |  |
Accumulated Deferred Tax Asset Valuation Allowance |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |
Accumulated other comprehensive loss, net of tax | 41.5 | 41.5 | 49.3 | $ 28.8 |  | $ 45.6
State [Member] |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |
Tax credit carryforwards | $ 11.0 | $ 11.0 |  |  |  |
Tax Cuts and Jobs Act, Transition Tax Liability |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |
Tax credit carryforwards |  |  | $ 28.2 |  |  |

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