| **Property, Plant and Equipment**            | 12 Months Ended                                                                                                                                                                                                                                                                                       |
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| **Property, Plant and Equipment [Abstract]** |                                                                                                                                                                                                                                                                                                  |
| Property, Plant and Equipment                | Property, Plant and EquipmentDecember 31 (dollars in millions)20212020Land$22.9 $11.6 Buildings377.0 349.2 Equipment805.8 729.7 Software137.5 132.1 1,343.2 1,222.6 Accumulated depreciation and amortization(736.5)(681.3)$606.7 $541.3  |

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| - References
No definition available.
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| - Definition
The entire disclosure for long-lived, physical asset used in normal conduct of business and not intended for resale. Includes, but is not limited to, work of art, historical treasure, and similar asset classified as collections.
+ References
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