| **Restructuring (Restructuring Charges and Reconciliation) (Details) - USD ($) $ in Millions** | 3 Months Ended | 12 Months Ended |
|------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Restructuring Cost and Reserve [Line Items]**                                                |           |            |   |   |
| Net cash proceeds from sale                                                                    |           | $ 0.7           | $ 2.8 | $ 3.8 |
| **Restructuring Reserve [Roll Forward]**                                                       |           |            |   |   |
| Balance at beginning of period                                                                 |           | 1.0             | 8.4 | 20.5 |
| Provision/(credits)                                                                            |           | 5.4             | (0.4) | 5.5 |
| Cash expenditures                                                                              |           | (4.9)           | (6.7) | (16.9) |
| Non-cash Items/ Currency Change                                                                |           |            | (0.3) | (0.7) |
| Balance at end of period                                                                       |           | 1.5             | 1.0 | 8.4 |
| Employee termination costs                                                                     |           |            |   |   |
| **Restructuring Reserve [Roll Forward]**                                                       |           |            |   |   |
| Balance at beginning of period                                                                 |           | 0.9             | 7.8 | 19.1 |
| Provision/(credits)                                                                            |           | 5.2             | (0.6) | 4.3 |
| Cash expenditures                                                                              |           | (4.7)           | (6.0) | (15.3) |
| Non-cash Items/ Currency Change                                                                |           |            | (0.3) | (0.3) |
| Balance at end of period                                                                       |           | $ 1.4           | 0.9 | 7.8 |
| Period over which restructuring and related costs are to be paid                               |           | 12 months       |   |   |
| Contract Termination                                                                           |           |            |   |   |
| **Restructuring Reserve [Roll Forward]**                                                       |           |            |   |   |
| Balance at beginning of period                                                                 |           | $ 0.1           | 0.6 | 1.4 |
| Provision/(credits)                                                                            |           | 0.2             | 0.2 | 0.5 |
| Cash expenditures                                                                              |           | (0.2)           | (0.7) | (1.5) |
| Non-cash Items/ Currency Change                                                                |           |            | 0.0 | 0.2 |
| Balance at end of period                                                                       |           | 0.1             | 0.1 | 0.6 |
| Termination of lease agreements                                                                |           |            |   |   |
| **Restructuring Cost and Reserve [Line Items]**                                                |           |            |   |   |
| Restructuring and Related Cost, Expected Cost                                                  |           | 1.0             |   |   |
| IT Contract Termination                                                                        |           |            |   |   |
| **Restructuring Cost and Reserve [Line Items]**                                                |           |            |   |   |
| Restructuring and Related Cost, Expected Cost                                                  |           | $ 0.7           |   |   |
| Asset impairment/net loss on disposal of assets resulting from restructuring activities        |           |            |   |   |
| **Restructuring Reserve [Roll Forward]**                                                       |           |            |   |   |
| Balance at beginning of period                                                                 |           |            | 0.0 | 0.0 |
| Provision/(credits)                                                                            |           |            |   | 0.6 |
| Cash expenditures                                                                              |           |            |   | 0.0 |
| Non-cash Items/ Currency Change                                                                |           |            |   | (0.6) |
| Balance at end of period                                                                       |           |            |   | 0.0 |
| Other                                                                                          |           |            |   |   |
| **Restructuring Reserve [Roll Forward]**                                                       |           |            |   |   |
| Balance at beginning of period                                                                 |           |            | $ 0.0 | 0.0 |
| Provision/(credits)                                                                            |           |            |   | 0.1 |
| Cash expenditures                                                                              |           |            |   | (0.1) |
| Non-cash Items/ Currency Change                                                                |           |            |   | 0.0 |
| Balance at end of period                                                                       |           |            |   | 0.0 |
| Buildings                                                                                      |           |            |   |   |
| **Restructuring Cost and Reserve [Line Items]**                                                |           |            |   |   |
| Net cash proceeds from sale                                                                    | $ 1.0          |            |   | $ 3.2 |

| X                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Restructuring and Related Costs, Payment Period
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount expected to be recognized in earnings for the specified restructuring cost.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.
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| - Definition
Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).
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