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Fair Value Measurements - Reconciliation of Level 3 Inputs (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Amount classified within accrued expenses and other payables | $ 0.0 | $ 0.0
Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Debt Instrument, Accrued Interest and Payables, Fair Value Disclosure | 0.0 |
Recurring | Level 3 |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Debt Instrument, Accrued Interest and Payables, Fair Value Disclosure | 0.0 |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance at the beginning of the period | 4.6 |
Balance at the end of the period | 0.0 |
Silverton 2016 | Recurring | Level 3 |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Distributed to third parties | (3.1) |
Third party |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Amount classified within accrued expenses and other payables | $ 0.0 | $ 0.0

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