Subsequent Events	3 Months Ended
Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn May 4, 2022, AFG announced a make-whole call to redeem all of its approximately $375 million in outstanding 3.50% Senior Notes due August 2026 on June 3, 2022. Management expects that the redemption of the 3.50% Senior Notes will result in a pretax loss on retirement of debt of less than $10 million in the second quarter of 2022. Concurrent with the debt retirement, AFG declared a special cash dividend of $8.00 per share of AFG Common Stock payable on May 27, 2022 to shareholders of record on May 20, 2022 (approximately $680 million in aggregate).

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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