| **Income Taxes (Narrative) (Details) - USD ($) $ in Millions** | 3 Months Ended | 6 Months Ended |        |        |
|----------------------------------------------------------------|----------------|----------------|--------|--------|
||
| **Income Tax Contingency [Line Items]**                        |           |           |   |   |   |   |
| Tax at statutory rate, percentage                              | 21.00%         | 21.00%         | 21.00% | 21.00% |   |   |
| Unrecognized Tax Benefits                                      | $ 34           |           | $ 34   |   |   | $ 34 |
| Cincinnati Global                                              |           |           |   |   |   |   |
| **Income Tax Contingency [Line Items]**                        |           |           |   |   |   |   |
| Net deferred tax assets                                        |           |           |   |   | $ 59 |   |
| Valuation allowance                                            |           |           |   |   | $ 55 |   |
| Operating Loss Carryforwards                                   | $ 178          |           | $ 178  |   |   |   |

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| - Definition
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Valuation Allowance
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| - Definition
Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.
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| - Definition
Percentage of domestic federal statutory tax rate applicable to pretax income (loss).
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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
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
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| - Definition
Amount of unrecognized tax benefits.
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