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v3.25.3

Long-Term Debt - Schedule of long-term debt (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Summary of Carrying value of long-term debt |  |
Principal | $ 1,848 | $ 1,498
Discount and Issue Costs | (28) | (23)
Carrying Value | 1,820 | 1,475
Senior Notes | AFG |  |
Summary of Carrying value of long-term debt |  |
Principal | 1,173 | 823
Discount and Issue Costs | (10) | (5)
Carrying Value | $ 1,163 | 818
Senior Notes | 4.50% Senior Notes due June 2047 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 4.50% |
Summary of Carrying value of long-term debt |  |
Principal | $ 567 | 567
Discount and Issue Costs | (1) | (1)
Carrying Value | $ 566 | 566
Senior Notes | 5.00% Senior Notes due September 2035 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 5.00% |
Summary of Carrying value of long-term debt |  |
Principal | $ 350 | 0
Discount and Issue Costs | (6) | 0
Carrying Value | $ 344 | 0
Senior Notes | 5.25% Senior Notes due April 2030 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 5.25% |
Summary of Carrying value of long-term debt |  |
Principal | $ 253 | 253
Discount and Issue Costs | (3) | (4)
Carrying Value | 250 | 249
Senior Notes | Other | AFG |  |
Summary of Carrying value of long-term debt |  |
Principal | 3 | 3
Discount and Issue Costs | 0 | 0
Carrying Value | 3 | 3
Subordinated Debentures | AFG |  |
Summary of Carrying value of long-term debt |  |
Principal | 675 | 675
Discount and Issue Costs | (18) | (18)
Carrying Value | $ 657 | 657
Subordinated Debentures | 4.50% Subordinated Debentures due September 2060 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 4.50% |
Summary of Carrying value of long-term debt |  |
Principal | $ 200 | 200
Discount and Issue Costs | (5) | (5)
Carrying Value | $ 195 | 195
Subordinated Debentures | 5.125% Subordinated Debentures due December 2059 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 5.125% |
Summary of Carrying value of long-term debt |  |
Principal | $ 200 | 200
Discount and Issue Costs | (5) | (5)
Carrying Value | $ 195 | 195
Subordinated Debentures | 5.625% Subordinated Debentures due June 2060 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 5.625% |
Summary of Carrying value of long-term debt |  |
Principal | $ 150 | 150
Discount and Issue Costs | (4) | (4)
Carrying Value | $ 146 | 146
Subordinated Debentures | 5.875% Subordinated Debentures due March 2059 | AFG |  |
Debt Instrument [Line Items] |  |
Interest rate on debt instruments | 5.875% |
Summary of Carrying value of long-term debt |  |
Principal | $ 125 | 125
Discount and Issue Costs | (4) | (4)
Carrying Value | $ 121 | $ 121

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