| **Long-Term Debt And Short-Term Borrowings (Narrative) (Details) € in Millions, $ in Millions, $ in Millions** |         |         |         | 9 Months Ended |        |         |         |
|----------------------------------------------------------------------------------------------------------------------|---------|---------|---------|----------------|--------|---------|---------|
||
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Payments for debt issuance costs                                                                                     |    |    |    | $ 3.3          | $ 0.6  |    |    |   |   |
| Total debt                                                                                                           |    |    |    | 923.5          |   |    | $ 888.0 |   |   |
| Five Year Senior Secured Credit Facility Maturing January 2022                                                       |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Debt Instrument, Term                                                                                                |    |    | 5 years |           |   |    |    |   |   |
| Secured Debt | Senior Secured Credit Facility Due May 2024                                                           |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Payments for debt issuance costs                                                                                     |    |    |    | 3.3            |   |    |    |   |   |
| Secured Debt | USD Senior Secured Term Loan A, due May 2024 (floating interest rate of 3.94% at September 30, 2019)  |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Total debt                                                                                                           | $ 100.0 |    |    | 98.7           |   |    | 0.0     |   |   |
| Secured Debt | Euro Term Loan A                                                                                      |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Debt Instrument, Face Amount                                                                                         |    |    | $ 320.8 |           |   |    |    | € 300.0 |   |
| Secured Debt | AUD Term Loan A                                                                                       |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Maximum borrowing capacity                                                                                           |    |    | 60.4    |           |   |    |    |   | $ 80.0 |
| Senior Notes | Senior Unsecured Notes, due December 2024 (fixed interest rate of 5.25%)                              |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Total debt                                                                                                           |    |    |    | 375.0          |   |    | $ 375.0 |   |   |
| Revolving Facility | Secured Debt                                                                                    |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Maximum borrowing capacity                                                                                           | 600.0   | $ 500.0 | $ 400.0 |           |   | $ 500.0 |    |   |   |
| Line of Credit Facility, Increase (Decrease), Net                                                                    | $ 200.0 | $ 100.0 |    |           |   |    |    |   |   |
| Total debt                                                                                                           |    |    |    | 132.4          |   |    |    |   |   |
| Amount available for borrowings under Senior Secured Revolving Credit Facilities                                     |    |    |    | 454.8          |   |    |    |   |   |
| Letters of credit outstanding                                                                                        |    |    |    | $ 12.8         |   |    |    |   |   |
| Senior Secured Credit Facility Due May 2024                                                                          |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Debt Instrument, Interest Rate, Increase (Decrease)                                                                  | (0.25%) |    |    |           |   |    |    |   |   |
| Senior Secured Credit Facility Due May 2024 | Secured Debt                                                           |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Debt Instrument, Minimum Leverage Ratio for Payments of Dividends or Repurchase of Shares                            | 3.25    |    |    |           |   | 2.50    |    |   |   |
| Minimum | Senior Secured Credit Facility Due May 2024 | Secured Debt                                                 |    |    |    |           |   |    |    |   |   |
| **Debt Instrument [Line Items]**                                                                                     |    |    |    |           |   |    |    |   |   |
| Consolidated Fixed Charge Coverage Ratio                                                                             |    |    |    |           |   | 1.25    |    |   |   |
| Interest Coverage Ratio                                                                                              | 3.00    |    |    |           |   |    |    |   |   |

| X                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Consolidated Fixed Charge Coverage Ratio
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| - Definition
Debt Instrument, Minimum Leverage Ratio for Payments of Dividends or Repurchase of Shares
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| X                                                                                                                                                                                                                         |
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| - Definition
Interest Coverage Ratio
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Face (par) amount of debt instrument at time of issuance.
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| X                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Incremental percentage increase (decrease) in the stated rate on a debt instrument.
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| X                                                                                                                                                                                                                                                                                                                                                                                                               |
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| - Definition
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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| X                                                                                                                                                                                                                                                                                                                                                                                                         |
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| - Definition
Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the aggregate of total long-term debt, including current maturities and short-term debt.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                        |
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| - Definition
The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) of the credit facility.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).
+ References
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| - Definition
The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.
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| X                                                                                                                                                                                   |
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| X                                                                                                                                              |
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| X                                                                                                                                                        |
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| X                                                                                                                       |
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