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Income Taxes - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Foreign tax credits | $ 8.2 |  | $ 0.0 |  |  | $ 8.2 | $ 0.0 |
Valuation allowance for deferred tax assets | 35.6 |  | 16.9 |  |  | 35.6 | 16.9 |
Amount of temporary difference due to repatriation of earnings from sale or liquidation of subsidiary | 317.1 |  |  |  |  | 317.1 |  |
Unrecognized tax benefits that, if recognized, would affect effective tax rate | 63.5 |  | 65.4 |  |  | 63.5 | 65.4 | $ 33.1
Accrued deferred tax assets for indirect tax benefits associated with uncertain tax positions | 26.3 |  | 27.4 |  |  | 26.3 | 27.4 |
Interest and penalties related to unrecognized tax benefits |  |  |  |  |  | 0.8 | 8.4 | 0.4
Accrued income tax interest and related charges | $ 11.4 |  | $ 10.5 |  |  | 11.4 | 10.5 |
Equity Method Investee |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Fair value assumptions, discount rate for performance based fees |  |  | 20.00% | 20.00% | 20.00% |  |  |
Income Tax Valuation Allowance |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Increase (decrease) in valuation allowance for deferred tax assets |  |  |  |  |  | $ 18.7 | $ (7.2) |
Minimum |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
State net operating loss carryforwards, expiration period |  |  |  |  |  | 10 years |  |
Foreign operating loss carryforwards, expiration period |  |  |  |  |  | 11 years |  |
Foreign tax credits, expiration period |  |  |  |  |  | 8 years |  |
Minimum | Equity Method Investee |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Fair value assumptions, discount rate for performance based fees | 20.00% | 20.00% |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
State net operating loss carryforwards, expiration period |  |  |  |  |  | 15 years |  |
Foreign operating loss carryforwards, expiration period |  |  |  |  |  | 19 years |  |
Foreign tax credits, expiration period |  |  |  |  |  | 10 years |  |
Non-US |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Expense recorded to reduce the carrying value of equity method affiliate |  |  |  |  |  |  |  | $ 240.0
State |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Operating loss carryforwards | $ 243.7 |  |  |  |  | $ 243.7 |  |
State | Operating Loss Carryforward |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Valuation allowance for deferred tax assets | 14.1 |  |  |  |  | 14.1 |  |
Foreign |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Operating loss carryforwards | 74.2 |  |  |  |  | 74.2 |  |
Foreign operating loss carryforward indefinitely | 9.6 |  |  |  |  | 9.6 |  |
Foreign | Operating Loss Carryforward |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Valuation allowance for deferred tax assets | 13.3 |  |  |  |  | 13.3 |  |
Foreign | Foreign Tax Credit Carryforward |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Valuation allowance for deferred tax assets | 8.2 |  |  |  |  | 8.2 |  |
Foreign | Expire over a 20-year period |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Operating loss carryforwards | $ 64.6 |  |  |  |  | $ 64.6 |  |

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