Statutory Accounting Information (Schedule Of Statutory Net Income And Statutory Surplus (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
The Cincinnati Insurance Company
Statutory Accounting Practices
Statutory net income	$ 520	$ 929	$ 466
Capital and surplus	6,512	7,247
The Cincinnati Casualty Company
Statutory Accounting Practices
Statutory net income	14	15	14
Capital and surplus	495	500
The Cincinnati Indemnity Company
Statutory Accounting Practices
Statutory net income	4	5	3
Capital and surplus	126	126
The Cincinnati Specialty Underwriters Insurance Company
Statutory Accounting Practices
Statutory net income	61	47	42
Capital and surplus	542	571
The Cincinnati Life Insurance Company
Statutory Accounting Practices
Statutory net income	64	41	$ 27
Capital and surplus	$ 326	$ 270

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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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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- Definition

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

+ References

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