Condensed Financial Statements Of Parent Company Condensed Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Condensed Financial Statements, Captions
Amortized cost of fixed maturities	$ 12,230	$ 11,312
Equity securities, cost	4,121	3,927
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	303	285
Cincinnati Financial Corporation
Condensed Financial Statements, Captions
Amortized cost of fixed maturities	64	69
Equity securities, cost	1,660	1,607
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 147	$ 138

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
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- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

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