| **Income Taxes (Narrative) (Details) - USD ($) $ in Millions** | 3 Months Ended | 9 Months Ended |        |
|----------------------------------------------------------------|----------------|----------------|--------|
||
| **Income Tax Disclosure**                                      |           |           |   |   |   |
| Tax at statutory rate, percentage                              | 21.00%         | 21.00%         | 21.00% | 21.00% |   |
| United States                                                  |           |           |   |   |   |
| **Income Tax Disclosure**                                      |           |           |   |   |   |
| Deferred tax assets valuation allowance                        | $ 0            |           | $ 0    |   | $ 0 |
| Cincinnati Global                                              |           |           |   |   |   |
| **Income Tax Disclosure**                                      |           |           |   |   |   |
| Deferred tax assets valuation allowance                        | 0              |           | 0      |   | 0 |
| Cincinnati Global | United States                              |           |           |   |   |   |
| **Income Tax Disclosure**                                      |           |           |   |   |   |
| Operating loss carryforwards                                   | 0              |           | 0      |   | 0 |
| Cincinnati Global | United Kingdom                             |           |           |   |   |   |
| **Income Tax Disclosure**                                      |           |           |   |   |   |
| Operating loss carryforwards                                   | $ 85           |           | $ 85   |   | $ 100 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of domestic federal statutory tax rate applicable to pretax income (loss).
+ References
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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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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
+ References
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| X                                                                                                                                                                       |
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