Schedule II. Condensed Financial Information of Registrant (Parent Company) (Narrative) (Details)	Dec. 31, 2019
CNAF Consolidated \| Loews
Condensed Financial Statements, Captions [Line Items]
Noncontrolling interest, ownership percentage by parent	89.00%

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.

No definition available.

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Period Type:	duration