Contingencies	6 Months Ended
Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Contingencies	ContingenciesThere have been no significant changes to the matters discussed and referred to in Note N — “Contingencies” of AFG’s 2020 Form 10-K, which covers property and casualty insurance reserves for claims related to environmental exposures, asbestos and other mass tort claims and environmental and occupational injury and disease claims of subsidiaries’ former railroad and manufacturing operations.

The entire disclosure for commitments and contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-URI http://asc.fasb.org/topic&trid=2127136

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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