Debt	9 Months Ended
Sep. 30, 2025
Debt Disclosure [Abstract]
Debt	Debt In August of 2025, CNA completed a public offering of $500 million aggregate principal amount of its 5.2% senior notes due August 15, 2035.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details