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Income Taxes - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Operating Loss Carryforwards [Line Items] |  |  |
Provisional one-time net benefit from changes in U.S. tax laws | $ 194.1 |  |
Net income tax benefit resulting from re-measurement of Company's deferred tax assets and liabilities | 216.9 |  |
Provisional amount for repatriation tax liability | $ 22.8 |  |
State net operating loss carryforwards, expiration period | 19 years |  |
Foreign operating loss carryforwards, expiration period | 20 years |  |
Operating loss carryforwards, valuation allowance | $ 24.1 | $ 22.1 |
Amount of temporary difference due to repatriation of earnings from sale or liquidation of subsidiary | 270.9 |  |
Unrecognized tax benefits that, if recognized, would affect effective tax rate | 32.4 | 26.0 | $ 25.3
Accrued income tax interest and related charges | 1.7 | 1.4 | $ 1.8
State and Local Jurisdiction |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards | 432.6 |  |
Foreign Tax Authority |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards | 61.5 |  |
Foreign Tax Authority | Valuation Allowance, Operating Loss Carryforwards |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards, valuation allowance | 24.1 |  |
Increase in valuation allowance, state net operating loss carryforward and realized deferred tax benefit | 2.0 | $ 1.6 |
Foreign Tax Authority | Expire over a 20-year period |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards | $ 51.8 |  |

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