Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 230
-SubTopic 10
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-Paragraph 2
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- References

No definition available.

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Long-Term Debt - Narrative (Details) - USD ($)	12 Months Ended
Long-Term Debt - Narrative (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2019
Long-term Debt, Fiscal Year Maturity [Abstract]
Scheduled principal payments on debt in next year	$ 0
Scheduled principal payments on debt in year two	0
Scheduled principal payments on debt in year three	0
Scheduled principal payments on debt in year four	0
Scheduled principal payments on debt in year five	0
Cash interest payments on long-term debt	65,000,000	$ 59,000,000	$ 85,000,000
AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Revolving credit line	500,000,000
Amount borrowed under AFG revolving credit facility	$ 0	$ 0
Interest rate description for revolving credit facility	1.00% to 1.875% (currently 1.375%) over LIBOR
LIBOR \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on revolving debt facility	1.375%
LIBOR \| AFG \| Minimum
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on revolving debt facility	1.00%
LIBOR \| AFG \| Maximum
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on revolving debt facility	1.875%
Senior Notes \| 4.50% Senior Notes due June 2047 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on debt instruments	4.50%
Senior Notes \| 3.50% Senior Notes due August 2026 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on debt instruments	3.50%
Subordinated Debt \| 5.125% Subordinated Debentures due December 2059 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Senior Notes, aggregate principal amount	$ 200,000,000
Interest rate on debt instruments	5.125%
Subordinated Debt \| 6% Subordinated Debentures due November 2055 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on debt instruments	6.00%
Subordinated Debt \| 5.875% Subordinated Debentures due March 2059 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Senior Notes, aggregate principal amount				$ 125,000,000
Interest rate on debt instruments	5.875%			5.875%
Subordinated Debt \| 6-1/4% Subordinated Debentures due September 2054 \| AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate on debt instruments	6.25%
Senior Notes, amount of the original debt instrument that was redeemed	$ 150,000,000