| **General (Narrative) (Details)**                                                | Mar. 31, 2024 |
|----------------------------------------------------------------------------------|---------------|
| CNAF Consolidated | Loews                                                        |          |
| **New Accounting Pronouncements or Change in Accounting Principle [Line Items]** |          |
| Noncontrolling interest, ownership percentage by parent                          | 92.00%        |

| X                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The parent entity's interest in net assets of the subsidiary, expressed as a percentage.
+ References
No definition available.
+ Details**Name:**us-gaap_MinorityInterestOwnershipPercentageByParent**Namespace Prefix:**us-gaap_**Data Type:**dtr-types:percentItemType**Balance Type:**na**Period Type:**instant |
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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.
+ References
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