| **Income Taxes - Reconciliation of Liability for Unrecognized Tax Benefits (Details) - USD ($) $ in Millions** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Gross Unrecognized Income Tax Benefits**                                                                     |            |   |   |
| Gross unrecognized income tax benefits, Beginning Balance                                                      | $ 2.9           | $ 0.9 | $ 1.1 |
| Gross amount of increases in unrecognized tax benefits related to prior periods                                | 0.3             | 1.7 | 0.7 |
| Gross amount of decreases in unrecognized tax benefits related to prior periods                                | (0.4)           |   | (0.9) |
| Gross amount of increases in unrecognized tax benefits related to current periods                              | 0.1             | 0.3 |   |
| Gross amount of decreases in unrecognized tax benefits related to current periods                              | (0.1)           |   |   |
| Gross unrecognized income tax benefits, Ending Balance                                                         | 2.8             | 2.9 | 0.9 |
| **Accrued Interest and Penalties**                                                                             |            |   |   |
| Unrecognized Tax Benefits, Accrued interest and penalties, Beginning Balance                                   | 0.0             | 0.0 | 0.3 |
| Gross amount of increases in unrecognized tax benefits related to prior periods                                | 0.0             | 0.0 | 0.1 |
| Gross amount of decreases in unrecognized tax benefits related to prior periods                                | 0.0             | 0.0 | (0.4) |
| Gross amount of increases in unrecognized tax benefits related to current period                               | 0.0             |   |   |
| Gross amount of decreases in unrecognized tax benefits related to current periods                              | 0.0             |   |   |
| Unrecognized Tax Benefits, Accrued interest and penalties, Ending Balance                                      | $ 0.0           | $ 0.0 | $ 0.0 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accrued interest and penalties associated with the gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accrued interest and penalties associated with the gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Unrecognized Tax Benefits Income Tax Penalties and Interest Accrued Decreases Resulting from Current Period Tax Positions
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accrued interest and penalties associated with the gross amount of increases in unrecognized tax benefits resulting from tax positions taken in current period tax returns, excluding amounts pertaining to tax returns.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrecognized tax benefits.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.
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| - Definition
Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.
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| - Definition
Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.
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