American Financial (AFG) 10-Q 11 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	May 01, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	1-13653
Entity Registrant Name	AMERICAN FINANCIAL GROUP, INC.
Entity Incorporation, State or Country Code	OH
Entity Tax Identification Number	31-1544320
Entity Central Index Key	0001042046
Entity Address, Address Line One	301 East Fourth Street
Entity Address, City or Town	Cincinnati
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	45202
City Area Code	513
Local Phone Number	579-2121
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		89,841,655
Entity Common Stock, Shares Outstanding Owned by Subsidiaries		14,900,000
Common stocks
Entity Information [Line Items]
Title of 12(b) Security	Common Stock
Trading Symbol	AFG
Security Exchange Name	NYSE
6% Subordinated Debentures due November 2055
Entity Information [Line Items]
Title of 12(b) Security	6% Subordinated Debentures due November 15, 2055
Trading Symbol	AFGH
Security Exchange Name	NYSE
5.875% Subordinated Debentures due in March 2059
Entity Information [Line Items]
Title of 12(b) Security	5.875% Subordinated Debentures due March 30, 2059
Trading Symbol	AFGB
Security Exchange Name	NYSE
5.125% Subordinated Debentures due December 2059
Entity Information [Line Items]
Title of 12(b) Security	5.125% Subordinated Debentures due December 15, 2059
Trading Symbol	AFGC
Security Exchange Name	NYSE

Consolidated Balance Sheet (Una

Consolidated Balance Sheet (Unaudited) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Assets:
Cash and cash equivalents	$ 1,673	$ 2,314
Investments:
Fixed maturities, available for sale at fair value (amortized cost — $46,101 and $44,524; allowance for expected credit losses of $61 at March 31, 2020)	46,134	46,505
Fixed maturities, trading at fair value	96	113
Equity securities, at fair value	1,559	1,937
Investments accounted for using the equity method	1,763	1,688
Mortgage loans	1,346	1,329
Policy loans	161	164
Equity index call options	209	924
Real estate and other investments	280	278
Total cash and investments	53,221	55,252
Recoverables from reinsurers	3,387	3,415
Prepaid reinsurance premiums	708	678
Agents’ balances and premiums receivable	1,302	1,335
Deferred policy acquisition costs	1,573	1,037
Assets of managed investment entities	67,643	70,130
Other receivables	981	975
Variable annuity assets (separate accounts)	497	628
Other assets	1,741	1,867
Goodwill	207	207
Total assets	67,643	70,130
Liabilities and Equity:
Unpaid losses and loss adjustment expenses	10,106	10,232
Unearned premiums	2,808	2,830
Annuity benefits accumulated	40,463	40,406
Life, accident and health reserves	607	612
Payable to reinsurers	779	814
Liabilities of managed investment entities	62,596	63,861
Long-term debt	1,473	1,473
Variable annuity liabilities (separate accounts)	497	628
Other liabilities	1,998	2,295
Total liabilities	62,596	63,861
Temporary equity
Redeemable noncontrolling interests	0	0
Shareholders’ equity:
Common Stock, no par value — 200,000,000 shares authorized — 89,827,336 and 90,303,686 shares outstanding	90	90
Capital surplus	1,309	1,307
Retained earnings	3,616	4,009
Accumulated other comprehensive income, net of tax	32	863
Total shareholders’ equity	5,047	6,269
Noncontrolling interests	0	0
Total equity	5,047	6,269
Total liabilities and equity	67,643	70,130
Variable interest entity, primary beneficiary
Investments:
Assets of managed investment entities	4,026	4,736
Total assets	4,026	4,736
Liabilities and Equity:
Liabilities of managed investment entities	3,865	4,571
Total liabilities	$ 3,865	$ 4,571

Consolidated Balance Sheet (U_2

Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Fixed maturities, available for sale at amortized cost	$ 46,101	$ 44,524
Fixed maturities, available for sale, allowance for expected credit losses	$ 61	$ 0
Common Stock, par value (USD per share)	$ 0	$ 0
Common Stock, shares authorized	200,000,000	200,000,000
Common Stock, shares outstanding	89,827,336	90,303,686

Consolidated Statement of Earni

Consolidated Statement of Earnings (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Revenues:
Property and casualty insurance net earned premiums	$ 1,209		$ 1,173
Net investment income	544	[1]	542
Realized gains (losses) on securities	(551)		184
Income (loss) of managed investment entities:
Investment income	59		69
Gain (loss) on change in fair value of assets/liabilities	(43)		0
Other income	57		56
Total revenues	1,275		2,024
Costs and Expenses:
Losses and loss adjustment expenses	707		692
Commissions and other underwriting expenses	420		399
Annuity benefits	276		311
Annuity and supplemental insurance acquisition expenses	113		28
Interest charges on borrowed money	17		16
Expenses of managed investment entities	48		55
Other expenses	82		110
Total costs and expenses	1,663		1,611
Earnings (loss) before income taxes	(388)		413
Provision (credit) for income taxes	(84)		87
Net earnings (loss), including noncontrolling interests	(304)		326
Less: Net earnings (loss) attributable to noncontrolling interests	(3)		(3)
Net Earnings (Loss) Attributable to Shareholders	$ (301)		$ 329
Earnings (Loss) Attributable to Shareholders per Common Share:
Basic (USD per share)	$ (3.34)		$ 3.68
Diluted (USD per share)	$ (3.34)		$ 3.63
Average number of Common Shares:
Basic (shares)	90.3		89.4
Diluted (shares)	90.3		90.7
Supplemental disclosure of Realized gains on securities:
Realized gains (losses) before impairments	$ (505)		$ 186
Losses on securities with impairment	(69)		(2)
Non-credit portion recognized in other comprehensive income (loss)	23		0
Impairment charges recognized in earnings	(46)		(2)
Total realized gains (losses) on securities	$ (551)		$ 184
[1]	Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings (loss), including noncontrolling interests	$ (304)	$ 326
Net unrealized gains (losses) on securities:
Unrealized holding gains (losses) on securities arising during the period	(865)	384
Reclassification adjustment for realized (gains) losses included in net earnings	19	(3)
Total net unrealized gains (losses) on securities	(846)	381
Net unrealized gains on cash flow hedges	27	11
Foreign currency translation adjustments	(10)	4
Other comprehensive income (loss), net of tax	(829)	396
Total comprehensive income (loss), net of tax	(1,133)	722
Less: Comprehensive income (loss) attributable to noncontrolling interests	(1)	(3)
Comprehensive income (loss) attributable to shareholders	$ (1,132)	$ 725

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Total	Common Shares	Common Stock and Capital Surplus	Retained Earnings	Accumulated Other Comp. Income (Loss)	Noncontrolling interests	Cumulative effect adjustment in period of adoptionRetained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	$ 4,972	$ 4,970		$ 1,334	$ 3,588	$ 48	$ 2
Beginning Balance, shares at Dec. 31, 2018			89,291,724
Beginning Balance at Dec. 31, 2018	4,972	4,970		1,334	3,588	48	2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	5,665	5,665		1,346	3,875	444	0
Net earnings (losses) attributable to parent	329	329			329
Net earnings (losses) including portion attributable to nonredeemable noncontrolling interest	329						0
Other comprehensive income (loss), attributable to parent		396				396
Other comprehensive income (loss) including portion attributable to nonredeemable noncontrolling interest	396
Dividends	(36)	(36)			(36)
Shares issued:
Exercise of stock options, shares			152,253
Exercise of stock options	6	6		6
Restricted stock awards, shares			232,565
Other benefit plans, shares			11,062
Other benefit plans	1	1		1
Dividend reinvestment plan, shares			1,893
Stock-based compensation expense	6	6		6
Shares exchanged — benefit plans, shares			(43,470)
Shares exchanged — benefit plans	(4)	(4)		(1)	(3)
Forfeitures of restricted stock, shares			(8,314)
Other	(5)	(3)			(3)		(2)
Ending Balance, shares at Mar. 31, 2019			89,637,713
Ending Balance at Mar. 31, 2019	5,665	5,665		1,346	3,875	444	0
Beginning Balance, Redeemable Noncontrolling Interests at Dec. 31, 2018	0
Redeemable Noncontrolling Interest, Equity, Carrying Amount [Abstract]
Net earnings attributable to redeemable noncontrolling interests	(3)
Other	3
Ending Balance, Redeemable Noncontrolling Interests at Mar. 31, 2019	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	5,665	5,665		1,346	3,875	444	0
Cumulative effect of accounting change	$ 6,269	6,269		1,397	4,009	863	0
Beginning Balance, shares at Dec. 31, 2019	90,303,686		90,303,686
Beginning Balance at Dec. 31, 2019	$ 6,269	6,269		1,397	4,009	863	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	5,047	5,047		1,399	3,616	32	0
Cumulative effect of accounting change | Accounting Standards Update 2016-13								$ 7
Net earnings (losses) attributable to parent	(301)	(301)			(301)
Net earnings (losses) including portion attributable to nonredeemable noncontrolling interest	(301)						0
Other comprehensive income (loss), attributable to parent		(831)				(831)
Other comprehensive income (loss) including portion attributable to nonredeemable noncontrolling interest	(831)
Dividends	(40)	(40)			(40)
Shares issued:
Exercise of stock options, shares			204,093
Exercise of stock options	9	9		9
Restricted stock awards, shares			227,867
Other benefit plans, shares			14,541
Other benefit plans	1	1		1
Dividend reinvestment plan, shares			1,617
Dividend reinvestment plan	0	0		0
Stock-based compensation expense	6	6		6
Shares acquired and retired, shares			(826,283)
Shares acquired and retired	(61)	(61)		(12)	(49)
Shares exchanged — benefit plans, shares			(95,854)
Shares exchanged — benefit plans	(11)	(11)		(2)	(9)
Forfeitures of restricted stock, shares			(2,331)
Other	$ (1)	(1)			(1)		0
Ending Balance, shares at Mar. 31, 2020	89,827,336		89,827,336
Ending Balance at Mar. 31, 2020	$ 5,047	5,047		1,399	3,616	32	0
Ending Balance (Accounting Standards Update 2016-13) at Mar. 31, 2020								7
Beginning Balance, Redeemable Noncontrolling Interests at Dec. 31, 2019	0
Redeemable Noncontrolling Interest, Equity, Carrying Amount [Abstract]
Net earnings attributable to redeemable noncontrolling interests	(3)
Other comprehensive income (loss) attributable to redeemable noncontrolling interests	2
Other	1
Ending Balance, Redeemable Noncontrolling Interests at Mar. 31, 2020	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change	$ 5,047	$ 5,047		$ 1,399	$ 3,616	$ 32	$ 0
Cumulative effect of accounting change | Accounting Standards Update 2016-13								$ 7

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Stockholders' Equity [Abstract]
Cash dividends per Common Share (USD per share)	$ 0.45	$ 0.40

Consolidated Statement of Cash

Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Activities:
Net earnings (loss), including noncontrolling interests	$ (304)	$ 326
Adjustments:
Depreciation and amortization	113	34
Annuity benefits	276	311
Realized (gains) losses on investing activities	550	(184)
Net sales of trading securities	8	1
Deferred annuity and life policy acquisition costs	(49)	(64)
Change in:
Reinsurance and other receivables	161	128
Other assets	410	(271)
Insurance claims and reserves	(152)	(112)
Payable to reinsurers	(35)	(22)
Other liabilities	(543)	304
Managed investment entities’ assets/liabilities	89	16
Other operating activities, net	8	(13)
Net cash provided by operating activities	532	454
Investing Activities:
Purchases of fixed maturities	(4,140)	(1,801)
Purchases of equity securities	(232)	(35)
Purchases of mortgage loans	(21)	(38)
Purchases of equity index call options and other investments	(245)	(220)
Purchases of real estate, property and equipment	(9)	(10)
Proceeds from maturities and redemptions of fixed maturities	1,220	1,032
Proceeds from repayments of mortgage loans	4	29
Proceeds from sales of fixed maturities	1,483	201
Proceeds from sales of equity securities	80	95
Proceeds from sales and settlements of equity index call options and other investments	248	79
Proceeds from sales of real estate, property and equipment	1	1
Managed investment entities:
Purchases of investments	(414)	(391)
Proceeds from sales and redemptions of investments	370	373
Other investing activities, net	2	1
Net cash used in investing activities	(1,653)	(684)
Financing Activities:
Annuity receipts	1,410	1,395
Annuity surrenders, benefits and withdrawals	(813)	(782)
Net transfers from variable annuity assets	15	13
Additional long-term borrowings	0	121
Retirements of managed investment entities’ liabilities	(41)	(3)
Issuances of Common Stock	10	7
Repurchases of Common Stock	(61)	0
Cash dividends paid on Common Stock	(40)	(36)
Net cash provided by financing activities	480	715
Net Change in Cash and Cash Equivalents	(641)	485
Cash and cash equivalents at beginning of period	2,314	1,515
Cash and cash equivalents at end of period	$ 1,673	$ 2,000

Accounting Policies

Accounting Policies	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Accounting Policies	Accounting Policies Basis of Presentation The accompanying consolidated financial statements for American Financial Group, Inc. and its subsidiaries (“AFG”) are unaudited; however, management believes that all adjustments (consisting only of normal recurring accruals unless otherwise disclosed herein) necessary for fair presentation have been made. The results of operations for interim periods are not necessarily indicative of results to be expected for the year. The financial statements have been prepared in accordance with the instructions to Form 10-Q and, therefore, do not include all information and footnotes necessary to be in conformity with U.S. generally accepted accounting principles (“GAAP”). Certain reclassifications have been made to prior periods to conform to the current year’s presentation. All significant intercompany balances and transactions have been eliminated. The results of operations of companies since their formation or acquisition are included in the consolidated financial statements. Events or transactions occurring subsequent to March 31, 2020 , and prior to the filing of this Form 10-Q, have been evaluated for potential recognition or disclosure herein. The preparation of the financial statements requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Changes in circumstances could cause actual results to differ materially from those estimates. Fair Value Measurements Accounting standards define fair value as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants on the measurement date. The standards establish a hierarchy of valuation techniques based on whether the assumptions that market participants would use in pricing the asset or liability (“inputs”) are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect AFG’s assumptions about the assumptions market participants would use in pricing the asset or liability. AFG did not have any material nonrecurring fair value measurements in the first three months of 2020 . Credit Losses on Financial Instruments On January 1, 2020, AFG adopted Accounting Standards Update (“ASU”) 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments , which provides a new loss model for determining credit-related impairments for financial instruments measured at amortized cost (mortgage loans, premiums receivable and reinsurance recoverables) and requires an entity to estimate the credit losses expected over the life of an exposure or pool of exposures. The estimate of expected credit losses considers historical information, current information, as well as reasonable and supportable forecasts, including estimates of prepayments. Expected credit losses, and subsequent increases or decreases in such expected losses, are recorded immediately through net earnings as an allowance that is deducted from the amortized cost basis of the financial asset, with the net carrying value of the financial asset presented on the balance sheet at the amount expected to be collected. AFG’s portfolio of mortgage loans crosses a wide variety of commercial properties with very strong loan to value ratios and no credit losses in recent years. In addition, the reinsurance used in AFG’s insurance operations is purchased from financially strong (highly rated) reinsurers and the Company has a long history of collecting premiums receivable through various economic cycles. At the date of adoption, the impact of adjusting AFG’s existing allowances for uncollectable mortgage loans, premiums receivable and reinsurance recoverables to the allowances calculated under the new guidance resulted in a reduction in the net allowance, which was recorded as the cumulative effect of an accounting change ( $7 million increase in retained earnings at January 1, 2020). The updated guidance also amended the current other-than-temporary impairment model for available for sale debt securities by requiring the recognition of impairments relating to credit losses through an allowance and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. Subsequent increases or decreases in expected credit losses will be recorded immediately in net earnings through realized gains (losses). Investments Equity securities other than those accounted for under the equity method are reported at fair value with holding gains and losses generally recorded in realized gains (losses) on securities. However, AFG records holding gains and losses on securities classified as “trading” under previous guidance, its small portfolio of limited partnerships and similar investments carried at fair value and certain other securities classified at purchase as “fair value through net investment income” in net investment income. Fixed maturity securities classified as “available for sale” are reported at fair value with unrealized gains and losses included in AOCI in AFG’s Balance Sheet. Fixed maturity securities classified as “trading” are reported at fair value with changes in unrealized holding gains or losses during the period included in net investment income. Mortgage and policy loans are carried primarily at the aggregate unpaid balance. Premiums and discounts on fixed maturity securities are amortized using the effective interest method. Mortgage-backed securities (“MBS”) are amortized over a period based on estimated future principal payments, including prepayments. Prepayment assumptions are reviewed periodically and adjusted to reflect actual prepayments and changes in expectations. Limited partnerships and similar investments are generally accounted for using the equity method of accounting. Under the equity method, AFG records its share of the earnings or losses of the investee based on when they are reported by the investee in its financial statements rather than in the period in which the investee declares a dividend. AFG’s share of the earnings or losses from equity method investments is generally recorded on a quarter lag due to the timing of the receipt of the investee’s financial statements. AFG’s equity in the earnings (losses) of limited partnerships and similar investments is included in net investment income. Realized gains or losses on the disposal of fixed maturity securities are determined on the specific identification basis. When a decline in the value of an available for sale fixed maturity is considered to be other-than-temporary at the balance sheet date, an allowance for credit losses (impairment), including any write-off of accrued interest, is charged to earnings (included in realized gains (losses) on securities). If management can assert that it does not intend to sell the security and it is not more likely than not that it will have to sell it before recovery of its amortized cost basis (net of allowance), then the impairment allowance is separated into two components: (i) the amount related to credit losses (recorded in earnings) and (ii) the amount related to all other factors (recorded in other comprehensive income). The credit-related portion is measured by comparing a security’s amortized cost to the present value of its current expected cash flows discounted at its effective yield prior to the charge. Both components are shown in the statement of earnings. If management intends to sell an impaired security, or it is more likely than not that it will be required to sell the security before recovery, an impairment is recorded in earnings to reduce the amortized cost (net of allowance) of that security to fair value. See “ Credit Losses on Financial Instruments ” above for a discussion of new guidance adopted on January 1, 2020. Derivatives Derivatives included in AFG’s Balance Sheet are recorded at fair value. Changes in fair value of derivatives are included in earnings unless the derivatives are designated and qualify as highly effective cash flow hedges. Derivatives that do not qualify for hedge accounting under GAAP consist primarily of (i) components of certain fixed maturity securities (primarily interest-only and principal-only MBS) and (ii) the equity-based component of certain annuity products (included in annuity benefits accumulated) and related equity index options designed to be consistent with the characteristics of the liabilities and used to mitigate the risk embedded in those annuity products. To qualify for hedge accounting, at the inception of a derivative contract, AFG formally documents the relationship between the terms of the hedge and the hedged items and its risk management objective. This documentation includes defining how hedge effectiveness and ineffectiveness will be measured on a retrospective and prospective basis. Changes in the fair value of derivatives that are designated and qualify as highly effective cash flow hedges are recorded in AOCI and are reclassified into earnings when the variability of the cash flows from the hedged items impacts earnings. When the change in the fair value of a qualifying cash flow hedge is included in earnings, it is included in the same line item in the statement of earnings as the cash flows from the hedged item. AFG uses interest rate swaps that are designated and qualify as highly effective cash flow hedges to mitigate interest rate risk related to certain floating-rate securities included in AFG’s portfolio of fixed maturity securities. Goodwill Goodwill represents the excess of cost of subsidiaries over AFG’s equity in their underlying net assets. Goodwill is not amortized, but is subject to an impairment test at least annually. An entity is not required to complete the quantitative annual goodwill impairment test on a reporting unit if the entity elects to perform a qualitative analysis and determines that it is more likely than not that the reporting unit’s fair value exceeds its carrying amount. Reinsurance Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policies. AFG’s property and casualty insurance subsidiaries report as assets (i) the estimated reinsurance recoverable on paid and unpaid losses, including an estimate for losses incurred but not reported, and (ii) amounts paid or due to reinsurers applicable to the unexpired terms of policies in force. Payable to reinsurers includes ceded premiums due to reinsurers, as well as ceded premiums retained by AFG’s property and casualty insurance subsidiaries under contracts to fund ceded losses as they become due. AFG’s insurance subsidiaries also assume reinsurance from other companies. Earnings on reinsurance assumed is recognized based on information received from ceding companies. An AFG subsidiary cedes life insurance policies to a third party on a funds withheld basis whereby the subsidiary retains the assets (securities) associated with the reinsurance contract. Interest is credited to the reinsurer based on the actual investment performance of the retained assets. This reinsurance contract is considered to contain an embedded derivative (that must be adjusted to fair value) because the yield on the payable is based on a specific block of the ceding company’s assets, rather than the overall creditworthiness of the ceding company. AFG determined that changes in the fair value of the underlying portfolio of fixed maturity securities is an appropriate measure of the value of the embedded derivative. The securities related to this contract are classified as “trading.” The adjustment to fair value on the embedded derivative offsets the investment income recorded on the adjustment to fair value of the related trading portfolio. Deferred Policy Acquisition Costs (“DPAC”) Policy acquisition costs (principally commissions, premium taxes and certain underwriting and policy issuance costs) directly related to the successful acquisition or renewal of an insurance contract are deferred. DPAC also includes capitalized costs associated with sales inducements offered to fixed annuity policyholders such as enhanced interest rates and premium and persistency bonuses. For the property and casualty companies, DPAC is limited based upon recoverability without any consideration for anticipated investment income and is charged against income ratably over the terms of the related policies. A premium deficiency is recognized if the sum of expected claims costs, claims adjustment expenses and unamortized acquisition costs exceed the related unearned premiums. A premium deficiency is first recognized by charging any unamortized acquisition costs to expense to the extent required to eliminate the deficiency. If the premium deficiency is greater than unamortized acquisition costs, a liability is accrued for the excess deficiency and reported with unpaid losses and loss adjustment expenses. DPAC related to annuities is deferred to the extent deemed recoverable and amortized, with interest, in relation to the present value of actual and expected gross profits on the policies. Expected gross profits consist principally of estimated future investment margin (estimated future net investment income less interest credited on policyholder funds) and surrender, mortality, and other life and annuity policy charges, less death, annuitization and guaranteed withdrawal benefits in excess of account balances and estimated future policy administration expenses. To the extent that realized gains and losses result in adjustments to the amortization of DPAC related to annuities, such adjustments are reflected as components of realized gains (losses) on securities. DPAC related to traditional life and health insurance is amortized over the expected premium paying period of the related policies, in proportion to the ratio of annual premium revenues to total anticipated premium revenues. See “ Life, Accident and Health Reserves ” below for details on the impact of loss recognition on the accounting for traditional life and health insurance contracts. DPAC includes the present value of future profits on business in force of annuity and life, accident and health insurance companies acquired (“PVFP”). PVFP represents the portion of the costs to acquire companies that is allocated to the value of the right to receive future cash flows from insurance contracts existing at the date of acquisition. PVFP is amortized with interest in relation to expected gross profits of the acquired policies for annuities and universal life products and in relation to the premium paying period for traditional life and health insurance products. DPAC and certain other balance sheet amounts related to annuity and life businesses are also adjusted, net of tax, for the change in expense that would have been recorded if the unrealized gains (losses) from securities had actually been realized. These adjustments are included in unrealized gains (losses) on marketable securities, a component of AOCI in AFG’s Balance Sheet. Managed Investment Entities A company is considered the primary beneficiary of, and therefore must consolidate, a variable interest entity (“VIE”) based primarily on its ability to direct the activities of the VIE that most significantly impact that entity’s economic performance and the obligation to absorb losses of, or receive benefits from, the entity that could potentially be significant to the VIE. AFG manages, and has investments in, collateralized loan obligations (“CLOs”) that are VIEs (see Note H — “ Managed Investment Entities ” ). AFG has determined that it is the primary beneficiary of these CLOs because (i) its role as asset manager gives it the power to direct the activities that most significantly impact the economic performance of the CLOs and (ii) through its investment in the CLO debt tranches, it has exposure to CLO losses (limited to the amount AFG invested) and the right to receive CLO benefits that could potentially be significant to the CLOs. Because AFG has no right to use the CLO assets and no obligation to pay the CLO liabilities, the assets and liabilities of the CLOs are shown separately in AFG’s Balance Sheet. AFG has elected the fair value option for reporting on the CLO assets and liabilities to improve the transparency of financial reporting related to the CLOs. The net gain or loss from accounting for the CLO assets and liabilities at fair value is presented separately in AFG’s Statement of Earnings. The fair values of a CLO’s assets may differ from the separately measured fair values of its liabilities even though the CLO liabilities only have recourse to the CLO assets. AFG has set the carrying value of the CLO liabilities equal to the fair value of the CLO assets (which have more observable fair values) as an alternative to reporting those liabilities at a separately measured fair value. CLO earnings attributable to AFG’s shareholders are measured by the change in the fair value of AFG’s investments in the CLOs and management fees earned. Unpaid Losses and Loss Adjustment Expenses The net liabilities stated for unpaid claims and for expenses of investigation and adjustment of unpaid claims represent management’s best estimate and are based upon (i) the accumulation of case estimates for losses reported prior to the close of the accounting period on direct business written; (ii) estimates received from ceding reinsurers and insurance pools and associations; (iii) estimates of unreported losses (including possible development on known claims) based on past experience; (iv) estimates based on experience of expenses for investigating and adjusting claims; and (v) the current state of the law and coverage litigation. Establishing reserves for asbestos, environmental and other mass tort claims involves considerably more judgment than other types of claims due to, among other things, inconsistent court decisions, an increase in bankruptcy filings as a result of asbestos-related liabilities, novel theories of coverage, and judicial interpretations that often expand theories of recovery and broaden the scope of coverage. Loss reserve liabilities are subject to the impact of changes in claim amounts and frequency and other factors. Changes in estimates of the liabilities for losses and loss adjustment expenses are reflected in the statement of earnings in the period in which determined. Despite the variability inherent in such estimates, management believes that the liabilities for unpaid losses and loss adjustment expenses are adequate. Annuity Benefits Accumulated Annuity receipts and benefit payments are recorded as increases or decreases in annuity benefits accumulated rather than as revenue and expense. Increases in this liability for interest credited are charged to annuity benefits expense and decreases for annuity policy charges are recorded in other income. For traditional fixed annuities, the liability for annuity benefits accumulated represents the account value that had accrued to the benefit of the policyholder as of the balance sheet date. For fixed-indexed annuities (“FIAs”), the liability for annuity benefits accumulated includes an embedded derivative that represents the estimated fair value of the index participation with the remaining component representing the discounted value of the guaranteed minimum contract benefits. For certain products, annuity benefits accumulated also includes reserves for accrued persistency and premium bonuses, guaranteed withdrawals and excess benefits expected to be paid on future deaths and annuitizations (“EDAR”). The liabilities for EDAR and guaranteed withdrawals are accrued for and modified using assumptions consistent with those used in determining DPAC and DPAC amortization, except that amounts are determined in relation to the present value of total expected assessments. Total expected assessments consist principally of estimated future investment margin, surrender, mortality, and other life and annuity policy charges, and unearned revenues once they are recognized as income. Annuity benefits accumulated also includes amounts advanced from the Federal Home Loan Bank of Cincinnati. Unearned Revenue Certain upfront policy charges on annuities are deferred as unearned revenue (included in other liabilities) and recognized in net earnings (included in other income) using the same assumptions and estimated gross profits used to amortize DPAC. Life, Accident and Health Reserves Liabilities for future policy benefits under traditional life, accident and health policies are computed using the net level premium method. Computations are based on the original projections of investment yields, mortality, morbidity and surrenders and include provisions for unfavorable deviations unless a loss recognition event (premium deficiency) occurs. Claim reserves and liabilities established for accident and health claims are modified as necessary to reflect actual experience and developing trends. For long-duration contracts (such as traditional life and long-term care policies), loss recognition occurs when, based on current expectations as of the measurement date, existing contract liabilities plus the present value of future premiums (including reasonably expected rate increases) are not expected to cover the present value of future claims payments and related settlement and maintenance costs (excluding overhead) as well as unamortized acquisition costs. If a block of business is determined to be in loss recognition, a charge is recorded in earnings in an amount equal to the excess of the present value of expected future claims costs and unamortized acquisition costs over existing reserves plus the present value of expected future premiums (with no provision for adverse deviation). The charge is recorded first to reduce unamortized acquisition costs and then as an additional reserve (if unamortized acquisition costs have been reduced to zero). In addition, reserves for traditional life and long-term care policies are subject to adjustment for loss recognition charges that would have been recorded if the unrealized gains (losses) from securities had actually been realized. This adjustment is included in unrealized gains (losses) on marketable securities, a component of AOCI in AFG’s Balance Sheet. Debt Issuance Costs Debt issuance costs related to AFG’s outstanding debt are presented in its Balance Sheet as a direct reduction in the carrying value of long-term debt and are amortized over the life of the related debt using the effective interest method as a component of interest expense. Debt issuance costs related to AFG’s revolving credit facilities are included in other assets in AFG’s Balance Sheet. Variable Annuity Assets and Liabilities Separate accounts related to variable annuities represent the fair value of deposits invested in underlying investment funds on which AFG earns a fee. Investment funds are selected and may be changed only by the policyholder, who retains all investment risk. AFG’s variable annuity contracts contain a guaranteed minimum death benefit (“GMDB”) to be paid if the policyholder dies before the annuity payout period commences. In periods of declining equity markets, the GMDB may exceed the value of the policyholder’s account. A GMDB liability is established for future excess death benefits using assumptions together with a range of reasonably possible scenarios for investment fund performance that are consistent with DPAC capitalization and amortization assumptions. Leases On January 1, 2019, AFG adopted ASU 2016-02, which requires entities that lease assets for terms longer than one year to recognize assets and liabilities for the rights and obligations created by those leases on the balance sheet based on the present value of contractual cash flows. The adoption of the new guidance did not have a material effect on AFG’s results of operations or liquidity. At March 31, 2020 AFG has a $182 million lease liability included in other liabilities and a lease right-of-use asset of $162 million included in other assets compared to $180 million and $158 million , respectively, at December 31, 2019 . Noncontrolling Interests For balance sheet purposes, noncontrolling interests represent the interests of shareholders other than AFG in consolidated entities. In the statement of earnings, net earnings and losses attributable to noncontrolling interests represents such shareholders’ interest in the earnings and losses of those entities. Noncontrolling interests that are redeemable at the option of the holder are presented separately in the mezzanine section of the balance sheet (between liabilities and equity). Premium Recognition Property and casualty premiums are earned generally over the terms of the policies on a pro rata basis. Unearned premiums represent that portion of premiums written, which is applicable to the unexpired terms of policies in force. On reinsurance assumed from other insurance companies or written through various underwriting organizations, unearned premiums are based on information received from such companies and organizations. For traditional life, accident and health products, premiums are recognized as revenue when legally collectible from policyholders. For interest-sensitive life and universal life products, premiums are recorded in a policyholder account, which is reflected as a liability. Revenue is recognized as amounts are assessed against the policyholder account for mortality coverage and contract expenses. Income Taxes Deferred income taxes are calculated using the liability method. Under this method, deferred income tax assets and liabilities are determined based on differences between financial reporting and tax bases and are measured using enacted tax rates. A valuation allowance is established to reduce total deferred tax assets to an amount that will more likely than not be realized. The effect of a change in tax rates on deferred tax assets and liabilities is recorded in net earnings in the period that includes the enactment date. AFG recognizes the tax benefits of uncertain tax positions only when the position is more likely than not to be sustained under examination by the appropriate taxing authority. Interest and penalties on AFG’s reserve for uncertain tax positions are recognized as a component of tax expense. Stock-Based Compensation All share-based grants are recognized as compensation expense on a straight-line basis over their vesting periods based on their calculated fair value at the date of grant. AFG uses the Black Scholes pricing model to measure the fair value of employee stock options. AFG records excess tax benefits or deficiencies for share-based payments through income tax expense in the statement of earnings. In addition, AFG accounts for forfeitures of awards when they occur. Benefit Plans AFG provides retirement benefits to qualified employees of participating companies through the AFG 401(k) Retirement and Savings Plan, a defined contribution plan. AFG makes all contributions to the retirement fund portion of the plan and matches a percentage of employee contributions to the savings fund. Company contributions are expensed in the year for which they are declared. AFG and many of its subsidiaries provide health care and life insurance benefits to eligible retirees. AFG also provides postemployment benefits to former or inactive employees (primarily those on disability) who were not deemed retired under other company plans. The projected future cost of providing these benefits is expensed over the period employees earn such benefits. Earnings Per Share Although basic earnings per share only considers shares of common stock outstanding during the period, the calculation of diluted earnings per share includes the following adjustments to weighted average common shares related to stock-based compensation plans: first three months of 2020 and 2019 — none and 1.3 million , respectively. There were 0.8 million anti-dilutive potential common shares for the first three months of 2020 due to AFG’s net loss and no anti-dilutive potential common shares for the first three months of 2019 . Statement of Cash Flows For cash flow purposes, “investing activities” are defined as making and collecting loans and acquiring and disposing of debt or equity instruments, property and equipment and businesses. “Financing activities” include obtaining resources from owners and providing them with a return on their investments, borrowing money and repaying amounts borrowed. Annuity receipts, surrenders, benefits and withdrawals are also reflected as financing activities. All other activities are considered “operating.” Short-term investments having original maturities of three months or less when purchased are considered to be cash equivalents for purposes of the financial statements

Acquisition of Business

Acquisition of Business	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Acquisition of Business	Acquisition of Business Effective in June 2019, National Interstate, a property and casualty insurance subsidiary of AFG, entered into an agreement with Atlas Financial Holdings, Inc. (“AFH”) to become the exclusive underwriter of AFH’s paratransit book of business. National Interstate estimates that the majority of AFH’s $110 million paratransit business will be eligible for quotation under this arrangement over the first 12 months following inception of the agreement. Under the terms of the agreement, AFH will act as an underwriting manager for National Interstate for at least 12 months, after which time National Interstate is entitled to acquire the renewal rights for the business from AFH for a purchase price equal to 15% of the in force gross written premiums at that date. The majority of the purchase price ultimately paid for the renewal rights will be recorded as an intangible renewal rights asset and will be amortized over the estimated life of the business acquired. In connection with the transaction, AFG was granted a five-year warrant to acquire approximately 2.4 million shares of AFH ( 19.9% at the acquisition date). The estimated fair value of the warrant was approximately $1 million at the date it was received.

Segments of Operations

Segments of Operations	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Segments of Operations	Segments of Operations AFG manages its business as three segments: (i) Property and casualty insurance, (ii) Annuity and (iii) Other, which includes holding company costs, revenues and costs of AFG’s limited insurance operations outside of property and casualty insurance and annuity segments, and operations attributable to the noncontrolling interests of the managed investment entities. AFG reports its property and casualty insurance business in the following Specialty sub-segments: (i) Property and transportation, which includes physical damage and liability coverage for buses and trucks, inland and ocean marine, agricultural-related products and other commercial property coverages, (ii) Specialty casualty, which includes primarily excess and surplus, executive and professional liability, general liability, umbrella and excess liability, specialty coverages in targeted markets, customized programs for small to mid-sized businesses and workers’ compensation insurance, and (iii) Specialty financial, which includes risk management insurance programs for lending and leasing institutions (including equipment leasing and collateral and lender-placed mortgage property insurance), fidelity and surety products and trade credit insurance. Premiums and underwriting profit included under Other specialty represent business assumed by AFG’s internal reinsurance program from the operations that make up AFG’s other Specialty sub-segments and amortization of deferred gains on retroactive reinsurance transactions related to the sales of businesses in prior years. AFG’s annuity business sells traditional fixed and indexed annuities in the retail, financial institutions, broker-dealer and registered investment advisor markets. AFG’s reportable segments and their components were determined based primarily upon similar economic characteristics, products and services. In December 2019, AFG initiated actions to exit the Lloyd’s of London insurance market, which included placing its Lloyd’s subsidiaries including its Lloyd’s Managing Agency, Neon Underwriting Ltd., into run-off. Neon and its predecessor, Marketform, have failed to achieve AFG’s profitability objectives since AFG’s purchase of Marketform in 2008. Beginning prospectively with the first quarter of 2020, the results for AFG’s Specialty casualty sub-segment exclude the run-off operations of Neon (“Neon exited lines”). The following tables (in millions) show AFG’s revenues and earnings before income taxes by segment and sub-segment. Three months ended March 31, 2020 2019 Revenues Property and casualty insurance: Premiums earned: Specialty Property and transportation $ 386 $ 361 Specialty casualty 556 629 Specialty financial 156 146 Other specialty 40 37 Other lines (a) 71 — Total premiums earned 1,209 1,173 Net investment income (b) 93 104 Other income 5 3 Total property and casualty insurance 1,307 1,280 Annuity: Net investment income 422 435 Other income 35 28 Total annuity 457 463 Other 62 97 Total revenues before realized gains (losses) 1,826 1,840 Realized gains (losses) on securities (551 ) 184 Total revenues $ 1,275 $ 2,024 (a) Represents premiums earned in the Neon exited lines during the first three months of 2020. Neon’s $88 million in earned premiums during the first three months of 2019 are included in the Specialty casualty sub-segment. (b) Includes a net loss of $6 million in the Neon exited lines, primarily from the change in fair value of equity securities. Three months ended March 31, 2020 2019 Earnings (Loss) Before Income Taxes Property and casualty insurance: Underwriting: Specialty Property and transportation $ 27 $ 39 Specialty casualty 52 36 Specialty financial 17 13 Other specialty (7 ) — Other lines (a) (2 ) (1 ) Total underwriting 87 87 Investment and other income, net (b) 84 95 Total property and casualty insurance 171 182 Annuity 29 90 Other (c) (37 ) (43 ) Total earnings before realized gains (losses) and income taxes 163 229 Realized gains (losses) on securities (551 ) 184 Total earnings (loss) before income taxes $ (388 ) $ 413 (a) Includes a $1 million underwriting loss in the first three months of 2020 in the Neon exited lines. Neon’s $10 million underwriting loss in the first three months of 2019 is included in the Specialty casualty sub-segment. (b) Includes $9 million in net expenses from the Neon exited lines, before noncontrolling interest. (c)

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Accounting standards for measuring fair value are based on inputs used in estimating fair value. The three levels of the hierarchy are as follows: Level 1 — Quoted prices for identical assets or liabilities in active markets (markets in which transactions occur with sufficient frequency and volume to provide pricing information on an ongoing basis). AFG’s Level 1 financial instruments consist primarily of publicly traded equity securities, highly liquid government bonds for which quoted market prices in active markets are available and short-term investments of managed investment entities. Level 2 — Quoted prices for similar instruments in active markets; quoted prices for identical or similar assets or liabilities in inactive markets (markets in which there are few transactions, the prices are not current, price quotations vary substantially over time or among market makers, or in which little information is released publicly); and valuations based on other significant inputs that are observable in active markets. AFG’s Level 2 financial instruments include separate account assets, corporate and municipal fixed maturity securities, asset-backed securities (“ABS”), mortgage-backed securities (“MBS”), certain non-affiliated common stocks, equity index options and investments of managed investment entities priced using observable inputs. Level 2 inputs include benchmark yields, reported trades, corroborated broker/dealer quotes, issuer spreads and benchmark securities. When non-binding broker quotes can be corroborated by comparison to similar securities priced using observable inputs, they are classified as Level 2. Level 3 — Valuations derived from market valuation techniques generally consistent with those used to estimate the fair values of Level 2 financial instruments in which one or more significant inputs are unobservable or when the market for a security exhibits significantly less liquidity relative to markets supporting Level 2 fair value measurements. The unobservable inputs may include management’s own assumptions about the assumptions market participants would use based on the best information available at the valuation date. Financial instruments whose fair value is estimated based on non-binding broker quotes or internally developed using significant inputs not based on, or corroborated by, observable market information are classified as Level 3. As discussed in Note A — “ Accounting Policies — Managed Investment Entities ,” AFG has set the carrying value of its CLO liabilities equal to the fair value of the CLO assets (which have more observable fair values) as an alternative to reporting those liabilities at separately measured fair values. As a result, the CLO liabilities are categorized within the fair value hierarchy on the same basis (proportionally) as the related CLO assets. Since the portion of the CLO liabilities allocated to Level 3 is derived from the fair value of the CLO assets, these amounts are excluded from the progression of Level 3 financial instruments. AFG’s management is responsible for the valuation process and uses data from outside sources (including nationally recognized pricing services and broker/dealers) in establishing fair value. AFG’s internal investment professionals are a group of approximately 20 analysts whose primary responsibility is to manage AFG’s investment portfolio. These professionals monitor individual investments as well as overall industries and are active in the financial markets on a daily basis. The group is led by AFG’s chief investment officer, who reports directly to one of AFG’s Co-CEOs. Valuation techniques utilized by pricing services and prices obtained from external sources are reviewed by AFG’s internal investment professionals who are familiar with the securities being priced and the markets in which they trade to ensure the fair value determination is representative of an exit price. To validate the appropriateness of the prices obtained, these investment managers consider widely published indices (as benchmarks), recent trades, changes in interest rates, general economic conditions and the credit quality of the specific issuers. In addition, the Company communicates directly with the pricing services regarding the methods and assumptions used in pricing, including verifying, on a test basis, the inputs used by the service to value specific securities. Assets and liabilities measured and carried at fair value in the financial statements are summarized below (in millions): Level 1 Level 2 Level 3 Total March 31, 2020 Assets: Available for sale (“AFS”) fixed maturities: U.S. Government and government agencies $ 158 $ 32 $ 15 $ 205 States, municipalities and political subdivisions — 6,801 105 6,906 Foreign government — 170 — 170 Residential MBS — 2,968 163 3,131 Commercial MBS — 875 32 907 Collateralized loan obligations — 3,970 168 4,138 Other asset-backed securities — 5,728 1,030 6,758 Corporate and other 25 22,346 1,548 23,919 Total AFS fixed maturities 183 42,890 3,061 46,134 Trading fixed maturities 1 95 — 96 Equity securities 1,056 67 436 1,559 Equity index call options — 209 — 209 Assets of managed investment entities (“MIE”) 169 3,841 16 4,026 Variable annuity assets (separate accounts) (*) — 497 — 497 Other assets — derivatives — 125 — 125 Total assets accounted for at fair value $ 1,409 $ 47,724 $ 3,513 $ 52,646 Liabilities: Liabilities of managed investment entities $ 162 $ 3,688 $ 15 $ 3,865 Derivatives in annuity benefits accumulated — — 3,099 3,099 Other liabilities — derivatives — 10 — 10 Total liabilities accounted for at fair value $ 162 $ 3,698 $ 3,114 $ 6,974 December 31, 2019 Assets: Available for sale fixed maturities: U.S. Government and government agencies $ 151 $ 43 $ 15 $ 209 States, municipalities and political subdivisions — 6,858 105 6,963 Foreign government — 172 — 172 Residential MBS — 2,987 173 3,160 Commercial MBS — 892 35 927 Collateralized loan obligations — 4,265 15 4,280 Other asset-backed securities — 5,842 1,286 7,128 Corporate and other 29 21,879 1,758 23,666 Total AFS fixed maturities 180 42,938 3,387 46,505 Trading fixed maturities 2 111 — 113 Equity securities 1,433 67 437 1,937 Equity index call options — 924 — 924 Assets of managed investment entities 213 4,506 17 4,736 Variable annuity assets (separate accounts) (*) — 628 — 628 Other assets — derivatives — 50 — 50 Total assets accounted for at fair value $ 1,828 $ 49,224 $ 3,841 $ 54,893 Liabilities: Liabilities of managed investment entities $ 206 $ 4,349 $ 16 $ 4,571 Derivatives in annuity benefits accumulated — — 3,730 3,730 Other liabilities — derivatives — 10 — 10 Total liabilities accounted for at fair value $ 206 $ 4,359 $ 3,746 $ 8,311 (*) Variable annuity liabilities equal the fair value of variable annuity assets. Approximately 7% of the total assets carried at fair value at March 31, 2020 , were Level 3 assets. Approximately 43% ( $1.52 billion ) of the Level 3 assets were priced using non-binding broker quotes, for which there is a lack of transparency as to the inputs used to determine fair value. Details as to the quantitative inputs are neither provided by the brokers nor otherwise reasonably obtainable by AFG. Internally developed Level 3 asset fair values represent approximately $1.63 billion at March 31, 2020 . Of this amount, approximately $727 million relates to fixed maturity securities that were priced using management’s best estimate of an appropriate credit spread over the treasury yield (of a similar duration) to discount future expected cash flows using a third-party model. The credit spread applied by management is the significant unobservable input. For this group of 37 securities, the average spread used was 414 basis points over the reference treasury yield and the spreads ranged from 53 basis points to 1,253 basis points (approximately 70% of the spreads were between 200 and 700 basis points). Had management used higher spreads, the fair value of this group of securities would have been lower. Conversely, if the spreads used were lower, the fair values would have been higher. For the remainder of the internally developed prices, any justifiable changes in unobservable inputs used to determine fair value would not have resulted in a material change in AFG’s financial position. The derivatives embedded in AFG’s fixed-indexed and variable-indexed annuity liabilities are measured using a discounted cash flow approach and had a fair value of $3.10 billion at March 31, 2020 . The following table presents information about the unobservable inputs used by management in determining fair value of these Level 3 liabilities. See Note F — “ Derivatives .” Unobservable Input Range Adjustment for insurance subsidiary’s credit risk 1.9% – 3.6% over the risk-free rate Risk margin for uncertainty in cash flows 0.80% reduction in the discount rate Surrenders 4% – 21% of indexed account value Partial surrenders 2% – 9% of indexed account value Annuitizations 0.1% – 1% of indexed account value Deaths 1.9% – 10.6% of indexed account value Budgeted option costs 2.5% – 3.3% of indexed account value The range of adjustments for insurance subsidiary’s credit risk is based on the Moody’s corporate A2 bond index and reflects credit spread variations across the yield curve. The range of projected surrender rates reflects the specific surrender charges and other features of AFG’s individual fixed-indexed and variable-indexed annuity products with an expected range of 7% to 10% in the majority of future calendar years ( 4% to 21% over all periods). Increasing the budgeted option cost or risk margin for uncertainty in cash flow assumptions in the table above would increase the fair value of the fixed-indexed and variable-indexed annuity embedded derivatives, while increasing any of the other unobservable inputs in the table above would decrease the fair value of the embedded derivatives. Changes in balances of Level 3 financial assets and liabilities carried at fair value during the first three months of 2020 and 2019 are presented below (in millions). The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. All transfers are reflected in the table at fair value as of the end of the reporting period. Total realized/unrealized gains (losses) included in Balance at December 31, 2019 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2020 AFS fixed maturities: U.S. government agency $ 15 $ 1 $ (1 ) $ — $ — $ — $ — $ 15 State and municipal 105 — 1 — (1 ) — — 105 Residential MBS 173 5 (12 ) — (5 ) 2 — 163 Commercial MBS 35 — — — (3 ) — — 32 Collateralized loan obligations 15 (7 ) 2 — — 158 — 168 Other asset-backed securities 1,286 (14 ) (11 ) 77 (178 ) 13 (143 ) 1,030 Corporate and other 1,758 (3 ) (27 ) 119 (36 ) 5 (268 ) 1,548 Total AFS fixed maturities 3,387 (18 ) (48 ) 196 (223 ) 178 (411 ) 3,061 Equity securities 437 (24 ) — 6 — 17 — 436 Assets of MIE 17 (1 ) — — — — — 16 Total Level 3 assets $ 3,841 $ (43 ) $ (48 ) $ 202 $ (223 ) $ 195 $ (411 ) $ 3,513 Embedded derivatives $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total Level 3 liabilities (*) $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2018 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2019 AFS fixed maturities: U.S. government agency $ 9 $ — $ — $ — $ (1 ) $ — $ — $ 8 State and municipal 59 — 5 — (1 ) — — 63 Residential MBS 197 5 (5 ) — (6 ) — (22 ) 169 Commercial MBS 56 — — — (1 ) — — 55 Collateralized loan obligations 116 — — — — — — 116 Other asset-backed securities 731 (3 ) 8 75 (114 ) — (143 ) 554 Corporate and other 1,996 2 31 432 (88 ) — (27 ) 2,346 Total AFS fixed maturities 3,164 4 39 507 (211 ) — (192 ) 3,311 Equity securities 336 1 — 1 — 16 — 354 Assets of MIE 21 (1 ) — — — — — 20 Total Level 3 assets $ 3,521 $ 4 $ 39 $ 508 $ (211 ) $ 16 $ (192 ) $ 3,685 Embedded derivatives $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) Total Level 3 liabilities (*) $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) (*) As previously discussed, these tables exclude the portion of MIE liabilities allocated to Level 3, which are derived from the fair value of the MIE assets. Fair Value of Financial Instruments The carrying value and fair value of financial instruments that are not carried at fair value in the financial statements are summarized below (in millions): Carrying Fair Value Value Total Level 1 Level 2 Level 3 March 31, 2020 Financial assets: Cash and cash equivalents $ 1,673 $ 1,673 $ 1,673 $ — $ — Mortgage loans 1,346 1,350 — — 1,350 Policy loans 161 161 — — 161 Total financial assets not accounted for at fair value $ 3,180 $ 3,184 $ 1,673 $ — $ 1,511 Financial liabilities: Annuity benefits accumulated (*) $ 40,218 $ 39,773 $ — $ — $ 39,773 Long-term debt 1,473 1,411 — 1,408 3 Total financial liabilities not accounted for at fair value $ 41,691 $ 41,184 $ — $ 1,408 $ 39,776 December 31, 2019 Financial assets: Cash and cash equivalents $ 2,314 $ 2,314 $ 2,314 $ — $ — Mortgage loans 1,329 1,346 — — 1,346 Policy loans 164 164 — — 164 Total financial assets not accounted for at fair value $ 3,807 $ 3,824 $ 2,314 $ — $ 1,510 Financial liabilities: Annuity benefits accumulated (*) $ 40,159 $ 40,182 $ — $ — $ 40,182 Long-term debt 1,473 1,622 — 1,619 3 Total financial liabilities not accounted for at fair value $ 41,632 $ 41,804 $ — $ 1,619 $ 40,185 (*) Excludes $245 million and $247 million of life contingent annuities in the payout phase at March 31, 2020 and December 31, 2019 , respectively.

Investments

Investments	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Available for sale fixed maturities at March 31, 2020 and December 31, 2019 , consisted of the following (in millions): Amortized Cost Allowance for Expected Credit Losses Gross Unrealized Net Unrealized Fair Value Gains Losses March 31, 2020 Fixed maturities: U.S. Government and government agencies $ 190 $ — $ 15 $ — $ 15 $ 205 States, municipalities and political subdivisions 6,526 — 388 (8 ) 380 6,906 Foreign government 164 — 6 — 6 170 Residential MBS 3,078 6 133 (74 ) 59 3,131 Commercial MBS 892 — 20 (5 ) 15 907 Collateralized loan obligations 4,456 17 5 (306 ) (301 ) 4,138 Other asset-backed securities 7,069 14 65 (362 ) (297 ) 6,758 Corporate and other 23,726 24 786 (569 ) 217 23,919 Total fixed maturities $ 46,101 $ 61 $ 1,418 $ (1,324 ) $ 94 $ 46,134 December 31, 2019 Fixed maturities: U.S. Government and government agencies $ 199 $ — $ 10 $ — $ 10 $ 209 States, municipalities and political subdivisions 6,604 — 363 (4 ) 359 6,963 Foreign government 170 — 3 (1 ) 2 172 Residential MBS 2,900 — 265 (5 ) 260 3,160 Commercial MBS 896 — 31 — 31 927 Collateralized loan obligations 4,307 — 10 (37 ) (27 ) 4,280 Other asset-backed securities 6,992 — 156 (20 ) 136 7,128 Corporate and other 22,456 — 1,231 (21 ) 1,210 23,666 Total fixed maturities $ 44,524 $ — $ 2,069 $ (88 ) $ 1,981 $ 46,505 Equity securities, which are reported at fair value with holding gains and losses recognized in net earnings, consisted of the following at March 31, 2020 and December 31, 2019 (in millions): March 31, 2020 December 31, 2019 Fair Value Fair Value Actual Cost over (under) Actual Cost over (under) Fair Value Cost Fair Value Cost Common stocks $ 1,315 $ 919 $ (396 ) $ 1,164 $ 1,283 $ 119 Perpetual preferred stocks 685 640 (45 ) 640 654 14 Total equity securities carried at fair value $ 2,000 $ 1,559 $ (441 ) $ 1,804 $ 1,937 $ 133 The following tables show gross unrealized losses (dollars in millions) on available for sale fixed maturities by investment category and length of time that individual securities have been in a continuous unrealized loss position at the following balance sheet dates. Less Than Twelve Months Twelve Months or More Unrealized Loss Fair Value Fair Value as % of Cost Unrealized Loss Fair Value Fair Value as % of Cost March 31, 2020 Fixed maturities: U.S. Government and government agencies $ — $ — — % $ — $ 1 100 % States, municipalities and political subdivisions (8 ) 235 97 % — 26 100 % Foreign government — 3 100 % — — — % Residential MBS (70 ) 1,562 96 % (4 ) 31 89 % Commercial MBS (5 ) 117 96 % — — — % Collateralized loan obligations (141 ) 2,234 94 % (165 ) 1,691 91 % Other asset-backed securities (352 ) 4,597 93 % (10 ) 94 90 % Corporate and other (554 ) 7,738 93 % (15 ) 98 87 % Total fixed maturities $ (1,130 ) $ 16,486 94 % $ (194 ) $ 1,941 91 % December 31, 2019 Fixed maturities: U.S. Government and government agencies $ — $ 16 100 % $ — $ 11 100 % States, municipalities and political subdivisions (3 ) 254 99 % (1 ) 82 99 % Foreign government (1 ) 70 99 % — — — % Residential MBS (4 ) 509 99 % (1 ) 69 99 % Commercial MBS — 17 100 % — — — % Collateralized loan obligations (11 ) 1,284 99 % (26 ) 1,728 99 % Other asset-backed securities (12 ) 1,211 99 % (8 ) 123 94 % Corporate and other (13 ) 1,100 99 % (8 ) 211 96 % Total fixed maturities $ (44 ) $ 4,461 99 % $ (44 ) $ 2,224 98 % At March 31, 2020 , the gross unrealized losses on fixed maturities of $1.32 billion relate to 1,871 securities. Investment grade securities (as determined by nationally recognized rating agencies) represented approximately 83% of the gross unrealized loss and 89% of the fair value. To evaluate fixed maturities for expected credit losses (impairment), management considers whether the unrealized loss is credit-driven or a result of changes in market interest rates, the extent to which fair value is less than cost basis, historical operating, balance sheet and cash flow data from the issuer, third party research and communications with industry specialists and discussions with issuer management. AFG analyzes its MBS securities for expected credit losses (impairment) each quarter based upon expected future cash flows. Management estimates expected future cash flows based upon its knowledge of the MBS market, cash flow projections (which reflect loan to collateral values, subordination, vintage and geographic concentration) received from independent sources, implied cash flows inherent in security ratings and analysis of historical payment data. In the first three months of 2020 , AFG recorded an allowance for credit losses of $6 million related to its residential MBS. In the first three months of 2020 , AFG recorded an allowance for credit losses of $24 million related to corporate bonds and other fixed maturities, $17 million on third-party collateralized loan obligations and $14 million on other asset-backed securities. Management believes AFG will recover its cost basis (net of any allowance) in the securities with unrealized losses and that AFG has the ability to hold the securities until they recover in value and had no intent to sell them at March 31, 2020 . See Note A — “ Accounting Policies — Credit Losses on Financial Instruments ,” for a discussion of new guidance effective January 1, 2020, which impacts the accounting for expected credit losses (impairments) of fixed maturity securities. Under the new guidance, credit losses on available for sale fixed maturities continue to be measured based on the present value of expected future cash flows compared to amortized cost; however, impairment losses are now recognized through an allowance instead of a direct writedown of amortized cost. Under the new guidance, recoveries of previously impaired amounts are recorded as an immediate reversal of all or a portion of the allowance instead of accredited as investment income through a yield adjustment. In addition, the allowance on available for sale fixed maturities cannot cause the amortized cost net of the allowance to be below fair value. Accordingly, future changes in the fair value of an impaired security (when the allowance was limited by the fair value) due to reasons other than issuer credit (e.g. changes in market interest rates) could result in increases or decreases in the allowance, which will be recorded through realized gains (losses) on securities. A progression of the allowance for expected credit losses on fixed maturity securities is shown below (in millions): 2020 Balance at January 1 $ — Impact of adoption of new accounting policy — Provision for expected credit losses 61 Reductions due to sales or redemptions — Balance at March 31 $ 61 The table below sets forth the scheduled maturities of available for sale fixed maturities as of March 31, 2020 (dollars in millions). Securities with sinking funds are reported at average maturity. Actual maturities may differ from contractual maturities because certain securities may be called or prepaid by the issuers. Amortized Fair Value Cost, net (*) Amount % Maturity One year or less $ 2,018 $ 2,027 4 % After one year through five years 10,563 10,710 23 % After five years through ten years 14,450 14,722 32 % After ten years 3,551 3,741 8 % 30,582 31,200 67 % Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years) 11,494 10,896 24 % MBS (average life of approximately 3-1/2 years) 3,964 4,038 9 % Total $ 46,040 $ 46,134 100 % (*) Amortized cost, net of allowance for expected credit losses. Certain risks are inherent in fixed maturity securities, including loss upon default, price volatility in reaction to changes in interest rates, and general market factors and risks associated with reinvestment of proceeds due to prepayments or redemptions in a period of declining interest rates. There were no investments in individual issuers that exceeded 10% of shareholders’ equity at March 31, 2020 or December 31, 2019 . Net Unrealized Gain on Marketable Securities In addition to adjusting fixed maturity securities classified as “available for sale” to fair value, GAAP requires that deferred policy acquisition costs and certain other balance sheet amounts related to annuity, long-term care and life businesses be adjusted to the extent that unrealized gains and losses from securities would result in adjustments to those balances had the unrealized gains or losses actually been realized. The following table shows (in millions) the components of the net unrealized gain on securities that is included in AOCI in AFG’s Balance Sheet. Pretax Deferred Tax Net March 31, 2020 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 124 $ (26 ) $ 98 Fixed maturities — all other (30 ) 7 (23 ) Total fixed maturities 94 (19 ) 75 Deferred policy acquisition costs — annuity segment (57 ) 12 (45 ) Annuity benefits accumulated (18 ) 3 (15 ) Unearned revenue 1 — 1 Total net unrealized gain on marketable securities $ 20 $ (4 ) $ 16 December 31, 2019 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 1,611 $ (338 ) $ 1,273 Fixed maturities — all other 370 (78 ) 292 Total fixed maturities 1,981 (416 ) 1,565 Deferred policy acquisition costs — annuity segment (681 ) 143 (538 ) Annuity benefits accumulated (219 ) 46 (173 ) Life, accident and health reserves (1 ) — (1 ) Unearned revenue 11 (2 ) 9 Total net unrealized gain on marketable securities $ 1,091 $ (229 ) $ 862 (*) Net unrealized gains on fixed maturity investments supporting AFG’s annuity benefits accumulated. Net Investment Income The following table shows (in millions) investment income earned and investment expenses incurred. Three months ended March 31, 2020 2019 Investment income: Fixed maturities $ 491 $ 469 Equity securities: Dividends 17 22 Change in fair value (a) (b) (12 ) 11 Equity in earnings of partnerships and similar investments 25 21 Other 28 25 Gross investment income 549 548 Investment expenses (5 ) (6 ) Net investment income (b) $ 544 $ 542 (a) Although the change in the fair value of the majority of AFG’s equity securities is recorded in realized gains (losses) on securities, AFG records holding gains and losses in net investment income on equity securities classified as “trading” under previous guidance and on a small portfolio of limited partnership and similar investments that do not qualify for the equity method of accounting. (b) Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income. Realized gains (losses) and changes in unrealized appreciation (depreciation) included in AOCI related to fixed maturity and equity security investments are summarized as follows (in millions): Three months ended March 31, 2020 Three months ended March 31, 2019 Realized gains (losses) Realized gains (losses) Before Impairments Impairment Allowance Total Change in Unrealized Before Impairments Impairments Total Change in Unrealized Fixed maturities $ 29 $ (61 ) $ (32 ) $ (1,887 ) $ 3 $ (3 ) $ — $ 853 Equity securities (535 ) — (535 ) — 182 — 182 — Mortgage loans and other investments 4 — 4 — — — — — Other (*) (3 ) 15 12 816 1 1 2 (370 ) Total pretax (505 ) (46 ) (551 ) (1,071 ) 186 (2 ) 184 483 Tax effects 106 10 116 225 (39 ) — (39 ) (102 ) Net of tax $ (399 ) $ (36 ) $ (435 ) $ (846 ) $ 147 $ (2 ) $ 145 $ 381 (*) Primarily adjustments to deferred policy acquisition costs and reserves related to the annuity business. All equity securities other than those accounted for under the equity method are carried at fair value through net earnings. AFG recorded net holding gains (losses) on equity securities during the first three months of 2020 and 2019 on securities that were still owned at March 31, 2020 and March 31, 2019 as follows (in millions): Three months ended March 31, 2020 2019 Included in realized gains (losses) $ (540 ) $ 163 Included in net investment income (5 ) 11 $ (545 ) $ 174 Gross realized gains and losses (excluding impairment write-downs and mark-to-market of derivatives) on available for sale fixed maturity investment transactions consisted of the following (in millions): Three months ended March 31, 2020 2019 Gross gains $ 29 $ 6 Gross losses (4 ) (9 )

Derivatives

Derivatives	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives As discussed under “ Derivatives ” in Note A — “ Accounting Policies ,” AFG uses derivatives in certain areas of its operations. Derivatives That Do Not Qualify for Hedge Accounting The following derivatives that do not qualify for hedge accounting under GAAP are included in AFG’s Balance Sheet at fair value (in millions): March 31, 2020 December 31, 2019 Derivative Balance Sheet Line Asset Liability Asset Liability MBS with embedded derivatives Fixed maturities $ 103 $ — $ 102 $ — Fixed-indexed and variable-indexed annuities (embedded derivative) Annuity benefits accumulated — 3,099 — 3,730 Equity index call options Equity index call options 209 — 924 — Equity index put options Other liabilities — 8 — 1 Reinsurance contracts (embedded derivative) Other liabilities — 2 — 4 $ 312 $ 3,109 $ 1,026 $ 3,735 The MBS with embedded derivatives consist of primarily interest-only and principal-only MBS. AFG records the entire change in the fair value of these securities in earnings. These investments are part of AFG’s overall investment strategy and represent a small component of AFG’s overall investment portfolio. Warrants to purchase shares of publicly traded companies, which represent a small component of AFG’s overall investment portfolio, are considered to be derivatives that are required to be carried at fair value through earnings. AFG’s fixed-indexed and variable-indexed annuities provide policyholders with a crediting rate tied, in part, to the performance of an existing stock market or other financial index. AFG attempts to mitigate the risk in the index-based component of these products through the purchase and sale of call and put options on the appropriate index. AFG receives collateral from certain counterparties to support its purchased call option assets (net of collateral required under put option contracts with the same counterparties). This collateral ( $76 million at March 31, 2020 and $577 million at December 31, 2019 ) is included in other assets in AFG’s Balance Sheet with an offsetting liability to return the collateral, which is included in other liabilities. AFG’s strategy is designed so that the net change in the fair value of the call option assets and put option liabilities will generally offset the economic change in the net liability from the index participation. Both the index-based component of the annuities (an embedded derivative) and the related call and put options are considered derivatives that must be adjusted for changes in fair value through earnings each period. The fair values of these derivatives are impacted by actual and expected stock market performance and interest rates as well as other factors. Fluctuations in certain of these factors, such as changes in interest rates and the performance of the stock market, are not economic in nature for the current reporting period, but rather impact the timing of reported results. As discussed under “ Reinsurance ” in Note A , AFG has a reinsurance contract that is considered to contain an embedded derivative. The following table summarizes the gains (losses) included in AFG’s Statement of Earnings for changes in the fair value of derivatives that do not qualify for hedge accounting for the first three months of 2020 and 2019 (in millions): Three months ended March 31, Derivative Statement of Earnings Line 2020 2019 MBS with embedded derivatives Realized gains (losses) on securities $ 4 $ 6 Fixed-indexed and variable-indexed annuities (embedded derivative) Annuity benefits 647 (462 ) Equity index call options Annuity benefits (628 ) 366 Equity index put options Annuity benefits (6 ) 1 Reinsurance contract (embedded derivative) Net investment income 2 (1 ) $ 19 $ (90 ) Derivatives Designated and Qualifying as Cash Flow Hedges As of March 31, 2020 , AFG has twelve active interest rate swaps that are designated and qualify as highly effective cash flow hedges to mitigate interest rate risk related to certain floating-rate securities included in AFG’s portfolio of fixed maturity securities. The purpose of each of these swaps is to effectively convert a portion of AFG’s floating-rate fixed maturity securities to fixed rates by offsetting the variability in cash flows attributable to changes in short-term LIBOR. Under the terms of the swaps, AFG receives fixed-rate interest payments in exchange for variable interest payments based on short-term LIBOR. The notional amounts of the interest rate swaps generally decline over each swap’s respective life (the swaps expire between April 2020 and June 2030) in anticipation of the expected decline in AFG’s portfolio of fixed maturity securities with floating interest rates based on short-term LIBOR. The total outstanding notional amount of AFG’s interest rate swaps was $1.86 billion at March 31, 2020 compared to $1.98 billion at December 31, 2019 , reflecting the scheduled amortization discussed above and the termination of a swap with a total notional amount of $83 million in the first quarter of 2020. The fair value of the interest rate swaps in an asset position and included in other assets was $125 million at March 31, 2020 and $50 million at December 31, 2019 . The fair value of the interest rate swaps in a liability position and included in other liabilities was less than $1 million at March 31, 2020 and $5 million at December 31, 2019 . The net unrealized gain or loss on cash flow hedges is included in AOCI, net of DPAC and deferred taxes. Amounts reclassified from AOCI (before DPAC and taxes) to net investment income were income of $12 million and income reductions of $2 million for the first three months of 2020 and 2019 , respectively. AFG had a $19 million liability to return collateral related to these swaps (included in other liabilities) at March 31, 2020 and a $20 million receivable for collateral posted related to these swaps (included in other assets) at December 31, 2019 .

Deferred Policy Acquisition Cos

Deferred Policy Acquisition Costs	3 Months Ended
	Mar. 31, 2020
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Costs	Deferred Policy Acquisition Costs A progression of deferred policy acquisition costs is presented below (in millions): P&C Annuity and Other Deferred Deferred Sales Consolidated Costs Costs Inducements PVFP Subtotal Unrealized (*) Total Total Balance at December 31, 2019 $ 322 $ 1,303 $ 75 $ 36 $ 1,414 $ (699 ) $ 715 $ 1,037 Additions 158 49 1 — 50 — 50 208 Amortization: Periodic amortization (170 ) (98 ) (3 ) (2 ) (103 ) — (103 ) (273 ) Included in realized gains — 10 — — 10 — 10 10 Foreign currency translation — — — — — — — — Change in unrealized — — — — — 591 591 591 Balance at March 31, 2020 $ 310 $ 1,264 $ 73 $ 34 $ 1,371 $ (108 ) $ 1,263 $ 1,573 Balance at December 31, 2018 $ 299 $ 1,285 $ 86 $ 42 $ 1,413 $ (30 ) $ 1,383 $ 1,682 Additions 187 64 1 — 65 — 65 252 Amortization: Periodic amortization (175 ) (15 ) (3 ) (2 ) (20 ) — (20 ) (195 ) Included in realized gains — 2 — — 2 — 2 2 Foreign currency translation 1 — — — — — — 1 Change in unrealized — — — — — (295 ) (295 ) (295 ) Balance at March 31, 2019 $ 312 $ 1,336 $ 84 $ 40 $ 1,460 $ (325 ) $ 1,135 $ 1,447 (*) Adjustments to DPAC related to net unrealized gains/losses on securities and cash flow hedges. The present value of future profits (“PVFP”) amounts in the table above are net of $156 million and $154 million of accumulated amortization at March 31, 2020 and December 31, 2019 , respectively.

Managed Investment Entities

Managed Investment Entities	3 Months Ended
	Mar. 31, 2020
Variable Interest Entity, Primary Beneficiary, Does Not Hold Majority Voting Interest, Disclosures [Abstract]
Managed Investment Entities	Managed Investment Entities AFG is the investment manager and its subsidiaries have investments ranging from 15.0% to 100.0% of the most subordinate debt tranche of eleven active collateralized loan obligation entities (“CLOs”), which are considered variable interest entities. AFG’s subsidiaries also own portions of the senior debt tranches of certain of these CLOs. Upon formation between 2012 and 2018, these entities issued securities in various senior and subordinate classes and invested the proceeds primarily in secured bank loans, which serve as collateral for the debt securities issued by each CLO. None of the collateral was purchased from AFG. AFG’s investments in the subordinate debt tranches of these entities receive residual income from the CLOs only after the CLOs pay expenses (including management fees to AFG) and interest on and returns of capital to senior levels of debt securities. There are no contractual requirements for AFG to provide additional funding for these entities. AFG has not provided and does not intend to provide any financial support to these entities. AFG’s maximum exposure to economic loss on the CLOs that it manages is limited to its investment in those CLOs, which had an aggregate fair value of $161 million (including $81 million invested in the most subordinate tranches) at March 31, 2020 , and $165 million at December 31, 2019 . During the first three months of 2020 , AFG subsidiaries purchased $57 million face amount of senior debt and subordinate tranches of existing CLOs for $39 million . During both the first three months of 2020 and 2019 , AFG subsidiaries received less than $1 million , in sale and redemption proceeds from its CLO investments. The revenues and expenses of the CLOs are separately identified in AFG’s Statement of Earnings, after the elimination of management fees and earnings attributable to shareholders of AFG as measured by the change in the fair value of AFG’s investments in the CLOs. Selected financial information related to the CLOs is shown below (in millions): Three months ended March 31, 2020 2019 Investment in CLO tranches at end of period $ 161 $ 193 Gains (losses) on change in fair value of assets/liabilities (a): Assets (679 ) 87 Liabilities 636 (87 ) Management fees paid to AFG 4 3 CLO earnings (losses) attributable to AFG shareholders (b) (36 ) 11 (a) Included in revenues in AFG’s Statement of Earnings. (b) Included in earnings before income taxes in AFG’s Statement of Earnings. The aggregate unpaid principal balance of the CLOs’ fixed maturity investments exceeded the fair value of the investments by $818 million and $146 million at March 31, 2020 and December 31, 2019 , respectively. The aggregate unpaid principal balance of the CLOs’ debt exceeded its carrying value by $747 million and $129 million at those dates. The CLO assets include loans with an aggregate fair value of $20 million at March 31, 2020 and $10 million at December 31, 2019 , for which the CLOs are not accruing interest because the loans are in default (aggregate unpaid principal balance of $50 million at March 31, 2020 and $25 million at December 31, 2019 ). In addition to the CLOs that it manages, AFG had investments in CLOs that are managed by third parties (therefore not consolidated), which are included in available for sale fixed maturity securities and had a carrying value of $4.14 billion at March 31, 2020 and $4.28 billion at December 31, 2019 .

Goodwill and Other Intangibles

Goodwill and Other Intangibles	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles	Goodwill and Other Intangibles There were no changes in the goodwill balance of $207 million during the first three months of 2020 . Included in other assets in AFG’s Balance Sheet is $40 million at March 31, 2020 and $43 million at December 31, 2019 in amortizable intangible assets related to property and casualty insurance acquisitions. These amounts are net of accumulated amortization of $53 million and $50 million , respectively. Amortization of intangibles was $3 million in both the first three months of 2020 and 2019 .

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following (in millions): March 31, 2020 December 31, 2019 Principal Discount and Issue Costs Carrying Value Principal Discount and Issue Costs Carrying Value Direct Senior Obligations of AFG: 4.50% Senior Notes due June 2047 $ 590 $ (2 ) $ 588 $ 590 $ (2 ) $ 588 3.50% Senior Notes due August 2026 425 (3 ) 422 425 (3 ) 422 Other 3 — 3 3 — 3 1,018 (5 ) 1,013 1,018 (5 ) 1,013 Direct Subordinated Obligations of AFG: 5.125% Subordinate Debentures due December 2059 200 (6 ) 194 200 (6 ) 194 6% Subordinated Debentures due November 2055 150 (5 ) 145 150 (5 ) 145 5.875% Subordinated Debentures due March 2059 125 (4 ) 121 125 (4 ) 121 475 (15 ) 460 475 (15 ) 460 $ 1,493 $ (20 ) $ 1,473 $ 1,493 $ (20 ) $ 1,473 AFG has no scheduled principal payments on its long-term debt for the balance of 2020 or in the subsequent five years. AFG can borrow up to $500 million under its revolving credit facility, which expires in June 2021. Amounts borrowed under this agreement bear interest at rates ranging from 1.00% to 1.875% (currently 1.375% ) over LIBOR based on AFG’s credit rating. No amounts were borrowed under this facility at March 31, 2020 or December 31, 2019

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity AFG is authorized to issue 12.5 million shares of Voting Preferred Stock and 12.5 million shares of Nonvoting Preferred Stock, each without par value. Accumulated Other Comprehensive Income, Net of Tax (“AOCI”) Comprehensive income is defined as all changes in shareholders’ equity except those arising from transactions with shareholders. Comprehensive income includes net earnings and other comprehensive income, which consists primarily of changes in net unrealized gains or losses on available for sale securities. The progression of the components of accumulated other comprehensive income follows (in millions): Other Comprehensive Income (Loss) AOCI Beginning Balance Pretax Tax Net of tax Attributable to noncontrolling interests Attributable to shareholders AOCI Ending Balance Three months ended March 31, 2020 Net unrealized gains (losses) on securities: Unrealized holding losses on securities arising during the period $ (1,095 ) $ 230 $ (865 ) $ — $ (865 ) Reclassification adjustment for realized (gains) losses included in net earnings (*) 24 (5 ) 19 — 19 Total net unrealized gains (losses) on securities $ 862 (1,071 ) 225 (846 ) — (846 ) $ 16 Net unrealized gains on cash flow hedges 17 34 (7 ) 27 — 27 44 Foreign currency translation adjustments (9 ) (10 ) — (10 ) (2 ) (12 ) (21 ) Pension and other postretirement plans adjustments (7 ) — — — — — (7 ) Total $ 863 $ (1,047 ) $ 218 $ (829 ) $ (2 ) $ (831 ) $ 32 Three months ended March 31, 2019 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 487 $ (103 ) $ 384 $ — $ 384 Reclassification adjustment for realized (gains) losses included in net earnings (*) (4 ) 1 (3 ) — (3 ) Total net unrealized gains on securities $ 83 483 (102 ) 381 — 381 $ 464 Net unrealized gains (losses) on cash flow hedges (11 ) 14 (3 ) 11 — 11 — Foreign currency translation adjustments (16 ) 4 — 4 — 4 (12 ) Pension and other postretirement plans adjustments (8 ) — — — — — (8 ) Total $ 48 $ 501 $ (105 ) $ 396 $ — $ 396 $ 444 (*) The reclassification adjustment out of net unrealized gains (losses) on securities affected the following lines in AFG’s Statement of Earnings: OCI component Affected line in the statement of earnings Pretax Realized gains (losses) on securities Tax Provision (credit) for income taxes Stock Incentive Plans Under AFG’s stock incentive plans, employees of AFG and its subsidiaries are eligible to receive equity awards in the form of stock options, stock appreciation rights, restricted stock awards, restricted stock units and stock awards. In the first three months of 2020 , AFG issued 227,867 shares of restricted Common Stock (fair value of $104.15 per share) under the Stock Incentive Plan. Total compensation expense related to stock incentive plans of AFG and its subsidiaries was $5 million and $6 million in the first three months of 2020 and 2019 , respectively.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following is a reconciliation of income taxes at the statutory rate of 21% to the provision for income taxes as shown in AFG’s Statement of Earnings (dollars in millions): Three months ended March 31, 2020 2019 Amount % of EBT Amount % of EBT Earnings (loss) before income taxes (“EBT”) $ (388 ) $ 413 Income taxes at statutory rate $ (81 ) 21 % $ 87 21 % Effect of: Stock-based compensation (4 ) 1 % (2 ) — % Tax exempt interest (3 ) 1 % (4 ) (1 %) Dividends received deduction (1 ) — % (1 ) — % Nondeductible expenses 2 (1 %) 2 — % Change in valuation allowance 2 (1 %) 2 — % Foreign operations 1 — % — — % Other — 1 % 3 1 % Provision (credit) for income taxes as shown in the statement of earnings $ (84 ) 22 % $ 87 21 % Approximately $23 million of AFG’s net operating loss carryforwards (“NOL”) subject to separate return limitation year (“SRLY”) tax rules will expire unutilized at December 31, 2020 . Since AFG maintains a full valuation allowance against its SRLY NOLs, the expiration of these loss carryforwards will be offset by a corresponding reduction in the valuation allowance and will have no overall impact on AFG’s income tax expense or results of operations.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies In December 2015, AFG completed the sale of substantially all of its run-off long-term care insurance business to HC2 Holdings, Inc. (“HC2”). As part of the transaction, AFG agreed to provide up to an aggregate of $35 million of capital support for the insurance companies, on an as-needed basis to maintain specified surplus levels, subject to immediate reimbursement by HC2 through a five-year capital maintenance agreement. As of March 31, 2020, AFG has been released of any obligation to perform under this agreement. Other than the matter described above, there have been no significant changes to the matters discussed and referred to in Note N — “Contingencies” of AFG’s 2019 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 former subsidiary railroad and manufacturing operations.

Insurance

Insurance	3 Months Ended
	Mar. 31, 2020
Insurance [Abstract]
Insurance	Insurance Property and Casualty Insurance Reserves The following table provides an analysis of changes in the liability for losses and loss adjustment expenses during the first three months of 2020 and 2019 (in millions): Three months ended March 31, 2020 2019 Balance at beginning of year $ 10,232 $ 9,741 Less reinsurance recoverables, net of allowance 3,024 2,942 Net liability at beginning of year 7,208 6,799 Provision for losses and LAE occurring in the current period 749 737 Net increase (decrease) in the provision for claims of prior years (42 ) (45 ) Total losses and LAE incurred (*) 707 692 Payments for losses and LAE of: Current year (75 ) (89 ) Prior years (676 ) (615 ) Total payments (751 ) (704 ) Foreign currency translation and other (22 ) 1 Net liability at end of period 7,142 6,788 Add back reinsurance recoverables, net of allowance 2,964 2,835 Gross unpaid losses and LAE included in the balance sheet at end of period $ 10,106 $ 9,623 (*) Includes $40 million in losses and LAE incurred in the Neon exited lines in the first three months of 2020 . The net decrease in the provision for claims of prior years during the first three months of 2020 reflects (i) lower than expected losses in the crop business and lower than anticipated claim frequency and severity at National Interstate (within the Property and transportation sub-segment) and (ii) lower than anticipated claim severity in the workers’ compensation businesses and lower than anticipated claim frequency and severity in the executive liability business (within the Specialty casualty sub-segment). This favorable development was partially offset by (i) higher than expected claim severity in the property and inland marine business (within the Property and transportation sub-segment), (ii) higher than expected claim frequency and severity in the excess and surplus lines businesses and higher than expected claim severity in the public sector business (within the Specialty casualty sub-segment), and (iii) higher than expected losses at Neon. The net decrease in the provision for claims of prior years during the first three months of 2019 reflects (i) lower than expected losses in the crop business and lower than expected claim frequency at National Interstate (all within the Property and transportation sub-segment), (ii) lower than anticipated claim severity in the workers’ compensation business (within the Specialty casualty sub-segment), and (iii) lower than expected claim frequency and severity in the surety business and lower than anticipated claim severity in the fidelity business (all within the Specialty financial sub-segment). This favorable development was partially offset higher than expected claim severity in the in the targeted markets businesses and higher than expected losses at Neon (all within the Specialty casualty sub-segment). Recoverables from Reinsurers and Premiums Receivable See Note A — “ Accounting Policies — Credit Losses on Financial Instruments ,” for a discussion of new guidance effective January 1, 2020, which impacts the accounting for expected credit losses of recoverables from reinsurers and premiums receivable. Progressions of the 2020 allowance for expected credit losses are shown below (in millions): Recoverables from Reinsurers Premiums Receivable Balance at January 1 $ 18 $ 13 Impact of adoption of new accounting policy (6 ) (3 ) Provision (credit) for expected credit losses 1 (1 ) Write-offs charged against the allowance — — Balance at March 31 $ 13 $ 9

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events Since March 31, 2020, the U.S. federal and state governments, along with governments around the world, have enacted emergency measures to reduce the spread of the COVID-19 pandemic. These actions have caused significant disruption in the global economy, which has prompted stabilization efforts including monetary and fiscal interventions. Some states have ordered or requested insurers to issue refunds or credits to policyholders with reduced exposures due to workforce reductions, travel limitations or otherwise diminished operations due to the pandemic. In addition, stay at home orders and other restrictions have reduced sales of annuities in the second quarter of 2020. Management cannot reliably estimate how long the pandemic and related recessionary economic conditions will last, whether the regulatory interventions will be successful or the ultimate impact on AFG’s financial condition, results of operations or liquidity. Because the majority of AFG’s investments in limited partnerships and similar investments accounted for under the equity method are reported on a quarter lag, AFG will likely record a loss from those investments in the second quarter of 2020 from the downturn in the financial markets that occurred in the first quarter. On April 2, 2020, AFG issued $300 million of 5.25% Senior Notes due in April 2030, which will increase liquidity and provide flexibility at the parent company in its response to the uncertainties of the current economic environment.

Accounting Policies (Policies)

Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements for American Financial Group, Inc. and its subsidiaries (“AFG”) are unaudited; however, management believes that all adjustments (consisting only of normal recurring accruals unless otherwise disclosed herein) necessary for fair presentation have been made. The results of operations for interim periods are not necessarily indicative of results to be expected for the year. The financial statements have been prepared in accordance with the instructions to Form 10-Q and, therefore, do not include all information and footnotes necessary to be in conformity with U.S. generally accepted accounting principles (“GAAP”). Certain reclassifications have been made to prior periods to conform to the current year’s presentation. All significant intercompany balances and transactions have been eliminated. The results of operations of companies since their formation or acquisition are included in the consolidated financial statements. Events or transactions occurring subsequent to March 31, 2020 , and prior to the filing of this Form 10-Q, have been evaluated for potential recognition or disclosure herein.
Fair Value Measurements	Fair Value Measurements Accounting standards for measuring fair value are based on inputs used in estimating fair value. The three levels of the hierarchy are as follows: Level 1 — Quoted prices for identical assets or liabilities in active markets (markets in which transactions occur with sufficient frequency and volume to provide pricing information on an ongoing basis). AFG’s Level 1 financial instruments consist primarily of publicly traded equity securities, highly liquid government bonds for which quoted market prices in active markets are available and short-term investments of managed investment entities. Level 2 — Quoted prices for similar instruments in active markets; quoted prices for identical or similar assets or liabilities in inactive markets (markets in which there are few transactions, the prices are not current, price quotations vary substantially over time or among market makers, or in which little information is released publicly); and valuations based on other significant inputs that are observable in active markets. AFG’s Level 2 financial instruments include separate account assets, corporate and municipal fixed maturity securities, asset-backed securities (“ABS”), mortgage-backed securities (“MBS”), certain non-affiliated common stocks, equity index options and investments of managed investment entities priced using observable inputs. Level 2 inputs include benchmark yields, reported trades, corroborated broker/dealer quotes, issuer spreads and benchmark securities. When non-binding broker quotes can be corroborated by comparison to similar securities priced using observable inputs, they are classified as Level 2. Level 3 — Valuations derived from market valuation techniques generally consistent with those used to estimate the fair values of Level 2 financial instruments in which one or more significant inputs are unobservable or when the market for a security exhibits significantly less liquidity relative to markets supporting Level 2 fair value measurements. The unobservable inputs may include management’s own assumptions about the assumptions market participants would use based on the best information available at the valuation date. Financial instruments whose fair value is estimated based on non-binding broker quotes or internally developed using significant inputs not based on, or corroborated by, observable market information are classified as Level 3. As discussed in Note A — “ Accounting Policies — Managed Investment Entities ,” AFG has set the carrying value of its CLO liabilities equal to the fair value of the CLO assets (which have more observable fair values) as an alternative to reporting those liabilities at separately measured fair values. As a result, the CLO liabilities are categorized within the fair value hierarchy on the same basis (proportionally) as the related CLO assets. Since the portion of the CLO liabilities allocated to Level 3 is derived from the fair value of the CLO assets, these amounts are excluded from the progression of Level 3 financial instruments. AFG’s management is responsible for the valuation process and uses data from outside sources (including nationally recognized pricing services and broker/dealers) in establishing fair value. AFG’s internal investment professionals are a group of approximately 20 analysts whose primary responsibility is to manage AFG’s investment portfolio. These professionals monitor individual investments as well as overall industries and are active in the financial markets on a daily basis. The group is led by AFG’s chief investment officer, who reports directly to one of AFG’s Co-CEOs. Valuation techniques utilized by pricing services and prices obtained from external sources are reviewed by AFG’s internal investment professionals who are familiar with the securities being priced and the markets in which they trade to ensure the fair value determination is representative of an exit price. To validate the appropriateness of the prices obtained, these investment managers consider widely published indices (as benchmarks), recent trades, changes in interest rates, general economic conditions and the credit quality of the specific issuers. In addition, the Company communicates directly with the pricing services regarding the methods and assumptions used in pricing, including verifying, on a test basis, the inputs used by the service to value specific securities.
Credit Losses on Financial Instruments	Credit Losses on Financial Instruments On January 1, 2020, AFG adopted Accounting Standards Update (“ASU”) 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Instruments , which provides a new loss model for determining credit-related impairments for financial instruments measured at amortized cost (mortgage loans, premiums receivable and reinsurance recoverables) and requires an entity to estimate the credit losses expected over the life of an exposure or pool of exposures. The estimate of expected credit losses considers historical information, current information, as well as reasonable and supportable forecasts, including estimates of prepayments. Expected credit losses, and subsequent increases or decreases in such expected losses, are recorded immediately through net earnings as an allowance that is deducted from the amortized cost basis of the financial asset, with the net carrying value of the financial asset presented on the balance sheet at the amount expected to be collected. AFG’s portfolio of mortgage loans crosses a wide variety of commercial properties with very strong loan to value ratios and no credit losses in recent years. In addition, the reinsurance used in AFG’s insurance operations is purchased from financially strong (highly rated) reinsurers and the Company has a long history of collecting premiums receivable through various economic cycles. At the date of adoption, the impact of adjusting AFG’s existing allowances for uncollectable mortgage loans, premiums receivable and reinsurance recoverables to the allowances calculated under the new guidance resulted in a reduction in the net allowance, which was recorded as the cumulative effect of an accounting change ( $7 million increase in retained earnings at January 1, 2020). The updated guidance also amended the current other-than-temporary impairment model for available for sale debt securities by requiring the recognition of impairments relating to credit losses through an allowance and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. Subsequent increases or decreases in expected credit losses will be recorded immediately in net earnings through realized gains (losses).
Investments	Investments Equity securities other than those accounted for under the equity method are reported at fair value with holding gains and losses generally recorded in realized gains (losses) on securities. However, AFG records holding gains and losses on securities classified as “trading” under previous guidance, its small portfolio of limited partnerships and similar investments carried at fair value and certain other securities classified at purchase as “fair value through net investment income” in net investment income. Fixed maturity securities classified as “available for sale” are reported at fair value with unrealized gains and losses included in AOCI in AFG’s Balance Sheet. Fixed maturity securities classified as “trading” are reported at fair value with changes in unrealized holding gains or losses during the period included in net investment income. Mortgage and policy loans are carried primarily at the aggregate unpaid balance. Premiums and discounts on fixed maturity securities are amortized using the effective interest method. Mortgage-backed securities (“MBS”) are amortized over a period based on estimated future principal payments, including prepayments. Prepayment assumptions are reviewed periodically and adjusted to reflect actual prepayments and changes in expectations. Limited partnerships and similar investments are generally accounted for using the equity method of accounting. Under the equity method, AFG records its share of the earnings or losses of the investee based on when they are reported by the investee in its financial statements rather than in the period in which the investee declares a dividend. AFG’s share of the earnings or losses from equity method investments is generally recorded on a quarter lag due to the timing of the receipt of the investee’s financial statements. AFG’s equity in the earnings (losses) of limited partnerships and similar investments is included in net investment income.
Derivatives	Derivatives Derivatives included in AFG’s Balance Sheet are recorded at fair value. Changes in fair value of derivatives are included in earnings unless the derivatives are designated and qualify as highly effective cash flow hedges. Derivatives that do not qualify for hedge accounting under GAAP consist primarily of (i) components of certain fixed maturity securities (primarily interest-only and principal-only MBS) and (ii) the equity-based component of certain annuity products (included in annuity benefits accumulated) and related equity index options designed to be consistent with the characteristics of the liabilities and used to mitigate the risk embedded in those annuity products. To qualify for hedge accounting, at the inception of a derivative contract, AFG formally documents the relationship between the terms of the hedge and the hedged items and its risk management objective. This documentation includes defining how hedge effectiveness and ineffectiveness will be measured on a retrospective and prospective basis. Changes in the fair value of derivatives that are designated and qualify as highly effective cash flow hedges are recorded in AOCI and are reclassified into earnings when the variability of the cash flows from the hedged items impacts earnings. When the change in the fair value of a qualifying cash flow hedge is included in earnings, it is included in the same line item in the statement of earnings as the cash flows from the hedged item. AFG uses interest rate swaps that are designated and qualify as highly effective cash flow hedges to mitigate interest rate risk related to certain floating-rate securities included in AFG’s portfolio of fixed maturity securities.
Goodwill	Goodwill Goodwill represents the excess of cost of subsidiaries over AFG’s equity in their underlying net assets. Goodwill is not amortized, but is subject to an impairment test at least annually. An entity is not required to complete the quantitative annual goodwill impairment test on a reporting unit if the entity elects to perform a qualitative analysis and determines that it is more likely than not that the reporting unit’s fair value exceeds its carrying amount.
Reinsurance	Reinsurance Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policies. AFG’s property and casualty insurance subsidiaries report as assets (i) the estimated reinsurance recoverable on paid and unpaid losses, including an estimate for losses incurred but not reported, and (ii) amounts paid or due to reinsurers applicable to the unexpired terms of policies in force. Payable to reinsurers includes ceded premiums due to reinsurers, as well as ceded premiums retained by AFG’s property and casualty insurance subsidiaries under contracts to fund ceded losses as they become due. AFG’s insurance subsidiaries also assume reinsurance from other companies. Earnings on reinsurance assumed is recognized based on information received from ceding companies. An AFG subsidiary cedes life insurance policies to a third party on a funds withheld basis whereby the subsidiary retains the assets (securities) associated with the reinsurance contract. Interest is credited to the reinsurer based on the actual investment performance of the retained assets. This reinsurance contract is considered to contain an embedded derivative (that must be adjusted to fair value) because the yield on the payable is based on a specific block of the ceding company’s assets, rather than the overall creditworthiness of the ceding company. AFG determined that changes in the fair value of the underlying portfolio of fixed maturity securities is an appropriate measure of the value of the embedded derivative. The securities related to this contract are classified as “trading.” The adjustment to fair value on the embedded derivative offsets the investment income recorded on the adjustment to fair value of the related trading portfolio.
Deferred Policy Acquisition Costs (“DPAC”)	Deferred Policy Acquisition Costs (“DPAC”) Policy acquisition costs (principally commissions, premium taxes and certain underwriting and policy issuance costs) directly related to the successful acquisition or renewal of an insurance contract are deferred. DPAC also includes capitalized costs associated with sales inducements offered to fixed annuity policyholders such as enhanced interest rates and premium and persistency bonuses. For the property and casualty companies, DPAC is limited based upon recoverability without any consideration for anticipated investment income and is charged against income ratably over the terms of the related policies. A premium deficiency is recognized if the sum of expected claims costs, claims adjustment expenses and unamortized acquisition costs exceed the related unearned premiums. A premium deficiency is first recognized by charging any unamortized acquisition costs to expense to the extent required to eliminate the deficiency. If the premium deficiency is greater than unamortized acquisition costs, a liability is accrued for the excess deficiency and reported with unpaid losses and loss adjustment expenses. DPAC related to annuities is deferred to the extent deemed recoverable and amortized, with interest, in relation to the present value of actual and expected gross profits on the policies. Expected gross profits consist principally of estimated future investment margin (estimated future net investment income less interest credited on policyholder funds) and surrender, mortality, and other life and annuity policy charges, less death, annuitization and guaranteed withdrawal benefits in excess of account balances and estimated future policy administration expenses. To the extent that realized gains and losses result in adjustments to the amortization of DPAC related to annuities, such adjustments are reflected as components of realized gains (losses) on securities. DPAC related to traditional life and health insurance is amortized over the expected premium paying period of the related policies, in proportion to the ratio of annual premium revenues to total anticipated premium revenues. See “ Life, Accident and Health Reserves ” below for details on the impact of loss recognition on the accounting for traditional life and health insurance contracts. DPAC includes the present value of future profits on business in force of annuity and life, accident and health insurance companies acquired (“PVFP”). PVFP represents the portion of the costs to acquire companies that is allocated to the value of the right to receive future cash flows from insurance contracts existing at the date of acquisition. PVFP is amortized with interest in relation to expected gross profits of the acquired policies for annuities and universal life products and in relation to the premium paying period for traditional life and health insurance products. DPAC and certain other balance sheet amounts related to annuity and life businesses are also adjusted, net of tax, for the change in expense that would have been recorded if the unrealized gains (losses) from securities had actually been realized. These adjustments are included in unrealized gains (losses) on marketable securities, a component of AOCI in AFG’s Balance Sheet.
Managed Investment Entities	Managed Investment Entities A company is considered the primary beneficiary of, and therefore must consolidate, a variable interest entity (“VIE”) based primarily on its ability to direct the activities of the VIE that most significantly impact that entity’s economic performance and the obligation to absorb losses of, or receive benefits from, the entity that could potentially be significant to the VIE. AFG manages, and has investments in, collateralized loan obligations (“CLOs”) that are VIEs (see Note H — “ Managed Investment Entities ” ). AFG has determined that it is the primary beneficiary of these CLOs because (i) its role as asset manager gives it the power to direct the activities that most significantly impact the economic performance of the CLOs and (ii) through its investment in the CLO debt tranches, it has exposure to CLO losses (limited to the amount AFG invested) and the right to receive CLO benefits that could potentially be significant to the CLOs. Because AFG has no right to use the CLO assets and no obligation to pay the CLO liabilities, the assets and liabilities of the CLOs are shown separately in AFG’s Balance Sheet. AFG has elected the fair value option for reporting on the CLO assets and liabilities to improve the transparency of financial reporting related to the CLOs. The net gain or loss from accounting for the CLO assets and liabilities at fair value is presented separately in AFG’s Statement of Earnings. The fair values of a CLO’s assets may differ from the separately measured fair values of its liabilities even though the CLO liabilities only have recourse to the CLO assets. AFG has set the carrying value of the CLO liabilities equal to the fair value of the CLO assets (which have more observable fair values) as an alternative to reporting those liabilities at a separately measured fair value. CLO earnings attributable to AFG’s shareholders are measured by the change in the fair value of AFG’s investments in the CLOs and management fees earned.
Unpaid Losses and Loss Adjustment Expenses	Unpaid Losses and Loss Adjustment Expenses The net liabilities stated for unpaid claims and for expenses of investigation and adjustment of unpaid claims represent management’s best estimate and are based upon (i) the accumulation of case estimates for losses reported prior to the close of the accounting period on direct business written; (ii) estimates received from ceding reinsurers and insurance pools and associations; (iii) estimates of unreported losses (including possible development on known claims) based on past experience; (iv) estimates based on experience of expenses for investigating and adjusting claims; and (v) the current state of the law and coverage litigation. Establishing reserves for asbestos, environmental and other mass tort claims involves considerably more judgment than other types of claims due to, among other things, inconsistent court decisions, an increase in bankruptcy filings as a result of asbestos-related liabilities, novel theories of coverage, and judicial interpretations that often expand theories of recovery and broaden the scope of coverage. Loss reserve liabilities are subject to the impact of changes in claim amounts and frequency and other factors. Changes in estimates of the liabilities for losses and loss adjustment expenses are reflected in the statement of earnings in the period in which determined. Despite the variability inherent in such estimates, management believes that the liabilities for unpaid losses and loss adjustment expenses are adequate.
Annuity Benefits Accumulated	Annuity Benefits Accumulated Annuity receipts and benefit payments are recorded as increases or decreases in annuity benefits accumulated rather than as revenue and expense. Increases in this liability for interest credited are charged to annuity benefits expense and decreases for annuity policy charges are recorded in other income. For traditional fixed annuities, the liability for annuity benefits accumulated represents the account value that had accrued to the benefit of the policyholder as of the balance sheet date. For fixed-indexed annuities (“FIAs”), the liability for annuity benefits accumulated includes an embedded derivative that represents the estimated fair value of the index participation with the remaining component representing the discounted value of the guaranteed minimum contract benefits. For certain products, annuity benefits accumulated also includes reserves for accrued persistency and premium bonuses, guaranteed withdrawals and excess benefits expected to be paid on future deaths and annuitizations (“EDAR”). The liabilities for EDAR and guaranteed withdrawals are accrued for and modified using assumptions consistent with those used in determining DPAC and DPAC amortization, except that amounts are determined in relation to the present value of total expected assessments. Total expected assessments consist principally of estimated future investment margin, surrender, mortality, and other life and annuity policy charges, and unearned revenues once they are recognized as income. Annuity benefits accumulated also includes amounts advanced from the Federal Home Loan Bank of Cincinnati.
Unearned Revenue	Unearned Revenue
Life, Accident and Health Reserves	Life, Accident and Health Reserves Liabilities for future policy benefits under traditional life, accident and health policies are computed using the net level premium method. Computations are based on the original projections of investment yields, mortality, morbidity and surrenders and include provisions for unfavorable deviations unless a loss recognition event (premium deficiency) occurs. Claim reserves and liabilities established for accident and health claims are modified as necessary to reflect actual experience and developing trends. For long-duration contracts (such as traditional life and long-term care policies), loss recognition occurs when, based on current expectations as of the measurement date, existing contract liabilities plus the present value of future premiums (including reasonably expected rate increases) are not expected to cover the present value of future claims payments and related settlement and maintenance costs (excluding overhead) as well as unamortized acquisition costs. If a block of business is determined to be in loss recognition, a charge is recorded in earnings in an amount equal to the excess of the present value of expected future claims costs and unamortized acquisition costs over existing reserves plus the present value of expected future premiums (with no provision for adverse deviation). The charge is recorded first to reduce unamortized acquisition costs and then as an additional reserve (if unamortized acquisition costs have been reduced to zero). In addition, reserves for traditional life and long-term care policies are subject to adjustment for loss recognition charges that would have been recorded if the unrealized gains (losses) from securities had actually been realized. This adjustment is included in unrealized gains (losses) on marketable securities, a component of AOCI in AFG’s Balance Sheet.
Debt Issuance Costs	Debt Issuance Costs
Variable Annuity Assets and Liabilities	Variable Annuity Assets and Liabilities Separate accounts related to variable annuities represent the fair value of deposits invested in underlying investment funds on which AFG earns a fee. Investment funds are selected and may be changed only by the policyholder, who retains all investment risk. AFG’s variable annuity contracts contain a guaranteed minimum death benefit (“GMDB”) to be paid if the policyholder dies before the annuity payout period commences. In periods of declining equity markets, the GMDB may exceed the value of the policyholder’s account. A GMDB liability is established for future excess death benefits using assumptions together with a range of reasonably possible scenarios for investment fund performance that are consistent with DPAC capitalization and amortization assumptions.
Leases	Leases On January 1, 2019, AFG adopted ASU 2016-02, which requires entities that lease assets for terms longer than one year to recognize assets and liabilities for the rights and obligations created by those leases on the balance sheet based on the present value of contractual cash flows. The adoption of the new guidance did not have a material effect on AFG’s results of operations or liquidity.
Noncontrolling Interests	Noncontrolling Interests For balance sheet purposes, noncontrolling interests represent the interests of shareholders other than AFG in consolidated entities. In the statement of earnings, net earnings and losses attributable to noncontrolling interests represents such shareholders’ interest in the earnings and losses of those entities. Noncontrolling interests that are redeemable at the option of the holder are presented separately in the mezzanine section of the balance sheet (between liabilities and equity).
Premium Recognition	Premium Recognition Property and casualty premiums are earned generally over the terms of the policies on a pro rata basis. Unearned premiums represent that portion of premiums written, which is applicable to the unexpired terms of policies in force. On reinsurance assumed from other insurance companies or written through various underwriting organizations, unearned premiums are based on information received from such companies and organizations. For traditional life, accident and health products, premiums are recognized as revenue when legally collectible from policyholders. For interest-sensitive life and universal life products, premiums are recorded in a policyholder account, which is reflected as a liability. Revenue is recognized as amounts are assessed against the policyholder account for mortality coverage and contract expenses.
Income Taxes	Income Taxes Deferred income taxes are calculated using the liability method. Under this method, deferred income tax assets and liabilities are determined based on differences between financial reporting and tax bases and are measured using enacted tax rates. A valuation allowance is established to reduce total deferred tax assets to an amount that will more likely than not be realized. The effect of a change in tax rates on deferred tax assets and liabilities is recorded in net earnings in the period that includes the enactment date. AFG recognizes the tax benefits of uncertain tax positions only when the position is more likely than not to be sustained under examination by the appropriate taxing authority. Interest and penalties on AFG’s reserve for uncertain tax positions are recognized as a component of tax expense.
Stock-Based Compensation	Stock-Based Compensation All share-based grants are recognized as compensation expense on a straight-line basis over their vesting periods based on their calculated fair value at the date of grant. AFG uses the Black Scholes pricing model to measure the fair value of employee stock options. AFG records excess tax benefits or deficiencies for share-based payments through income tax expense in the statement of earnings. In addition, AFG accounts for forfeitures of awards when they occur.
Benefit Plans	Benefit Plans AFG provides retirement benefits to qualified employees of participating companies through the AFG 401(k) Retirement and Savings Plan, a defined contribution plan. AFG makes all contributions to the retirement fund portion of the plan and matches a percentage of employee contributions to the savings fund. Company contributions are expensed in the year for which they are declared. AFG and many of its subsidiaries provide health care and life insurance benefits to eligible retirees. AFG also provides postemployment benefits to former or inactive employees (primarily those on disability) who were not deemed retired under other company plans. The projected future cost of providing these benefits is expensed over the period employees earn such benefits.
Earnings Per Share	Earnings Per Share Although basic earnings per share only considers shares of common stock outstanding during the period, the calculation of diluted earnings per share includes the following adjustments to weighted average common shares related to stock-based compensation plans: first three months of 2020 and 2019 — none and 1.3 million , respectively.
Statement of Cash Flows	Statement of Cash Flows For cash flow purposes, “investing activities” are defined as making and collecting loans and acquiring and disposing of debt or equity instruments, property and equipment and businesses. “Financing activities” include obtaining resources from owners and providing them with a return on their investments, borrowing money and repaying amounts borrowed. Annuity receipts, surrenders, benefits and withdrawals are also reflected as financing activities. All other activities are considered “operating.” Short-term investments having original maturities of three months or less when purchased are considered to be cash equivalents for purposes of the financial statements
Segments of Operations	AFG reports its property and casualty insurance business in the following Specialty sub-segments: (i) Property and transportation, which includes physical damage and liability coverage for buses and trucks, inland and ocean marine, agricultural-related products and other commercial property coverages, (ii) Specialty casualty, which includes primarily excess and surplus, executive and professional liability, general liability, umbrella and excess liability, specialty coverages in targeted markets, customized programs for small to mid-sized businesses and workers’ compensation insurance, and (iii) Specialty financial, which includes risk management insurance programs for lending and leasing institutions (including equipment leasing and collateral and lender-placed mortgage property insurance), fidelity and surety products and trade credit insurance. Premiums and underwriting profit included under Other specialty represent business assumed by AFG’s internal reinsurance program from the operations that make up AFG’s other Specialty sub-segments and amortization of deferred gains on retroactive reinsurance transactions related to the sales of businesses in prior years. AFG’s annuity business sells traditional fixed and indexed annuities in the retail, financial institutions, broker-dealer and registered investment advisor markets. AFG’s reportable segments and their components were determined based primarily upon similar economic characteristics, products and services.
Net Unrealized Gain on Marketable Securities	Net Unrealized Gain on Marketable Securities
Accumulated Other Comprehensive Income, Net of Tax (“AOCI”)	Accumulated Other Comprehensive Income, Net of Tax (“AOCI”)

Segments of Operations (Tables)

Segments of Operations (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Segment Reporting Information, by Segment	The following tables (in millions) show AFG’s revenues and earnings before income taxes by segment and sub-segment. Three months ended March 31, 2020 2019 Revenues Property and casualty insurance: Premiums earned: Specialty Property and transportation $ 386 $ 361 Specialty casualty 556 629 Specialty financial 156 146 Other specialty 40 37 Other lines (a) 71 — Total premiums earned 1,209 1,173 Net investment income (b) 93 104 Other income 5 3 Total property and casualty insurance 1,307 1,280 Annuity: Net investment income 422 435 Other income 35 28 Total annuity 457 463 Other 62 97 Total revenues before realized gains (losses) 1,826 1,840 Realized gains (losses) on securities (551 ) 184 Total revenues $ 1,275 $ 2,024 (a) Represents premiums earned in the Neon exited lines during the first three months of 2020. Neon’s $88 million in earned premiums during the first three months of 2019 are included in the Specialty casualty sub-segment. (b) Includes a net loss of $6 million in the Neon exited lines, primarily from the change in fair value of equity securities. Three months ended March 31, 2020 2019 Earnings (Loss) Before Income Taxes Property and casualty insurance: Underwriting: Specialty Property and transportation $ 27 $ 39 Specialty casualty 52 36 Specialty financial 17 13 Other specialty (7 ) — Other lines (a) (2 ) (1 ) Total underwriting 87 87 Investment and other income, net (b) 84 95 Total property and casualty insurance 171 182 Annuity 29 90 Other (c) (37 ) (43 ) Total earnings before realized gains (losses) and income taxes 163 229 Realized gains (losses) on securities (551 ) 184 Total earnings (loss) before income taxes $ (388 ) $ 413 (a) Includes a $1 million underwriting loss in the first three months of 2020 in the Neon exited lines. Neon’s $10 million underwriting loss in the first three months of 2019 is included in the Specialty casualty sub-segment. (b) Includes $9 million in net expenses from the Neon exited lines, before noncontrolling interest. (c)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value	Assets and liabilities measured and carried at fair value in the financial statements are summarized below (in millions): Level 1 Level 2 Level 3 Total March 31, 2020 Assets: Available for sale (“AFS”) fixed maturities: U.S. Government and government agencies $ 158 $ 32 $ 15 $ 205 States, municipalities and political subdivisions — 6,801 105 6,906 Foreign government — 170 — 170 Residential MBS — 2,968 163 3,131 Commercial MBS — 875 32 907 Collateralized loan obligations — 3,970 168 4,138 Other asset-backed securities — 5,728 1,030 6,758 Corporate and other 25 22,346 1,548 23,919 Total AFS fixed maturities 183 42,890 3,061 46,134 Trading fixed maturities 1 95 — 96 Equity securities 1,056 67 436 1,559 Equity index call options — 209 — 209 Assets of managed investment entities (“MIE”) 169 3,841 16 4,026 Variable annuity assets (separate accounts) (*) — 497 — 497 Other assets — derivatives — 125 — 125 Total assets accounted for at fair value $ 1,409 $ 47,724 $ 3,513 $ 52,646 Liabilities: Liabilities of managed investment entities $ 162 $ 3,688 $ 15 $ 3,865 Derivatives in annuity benefits accumulated — — 3,099 3,099 Other liabilities — derivatives — 10 — 10 Total liabilities accounted for at fair value $ 162 $ 3,698 $ 3,114 $ 6,974 December 31, 2019 Assets: Available for sale fixed maturities: U.S. Government and government agencies $ 151 $ 43 $ 15 $ 209 States, municipalities and political subdivisions — 6,858 105 6,963 Foreign government — 172 — 172 Residential MBS — 2,987 173 3,160 Commercial MBS — 892 35 927 Collateralized loan obligations — 4,265 15 4,280 Other asset-backed securities — 5,842 1,286 7,128 Corporate and other 29 21,879 1,758 23,666 Total AFS fixed maturities 180 42,938 3,387 46,505 Trading fixed maturities 2 111 — 113 Equity securities 1,433 67 437 1,937 Equity index call options — 924 — 924 Assets of managed investment entities 213 4,506 17 4,736 Variable annuity assets (separate accounts) (*) — 628 — 628 Other assets — derivatives — 50 — 50 Total assets accounted for at fair value $ 1,828 $ 49,224 $ 3,841 $ 54,893 Liabilities: Liabilities of managed investment entities $ 206 $ 4,349 $ 16 $ 4,571 Derivatives in annuity benefits accumulated — — 3,730 3,730 Other liabilities — derivatives — 10 — 10 Total liabilities accounted for at fair value $ 206 $ 4,359 $ 3,746 $ 8,311 (*) Variable annuity liabilities equal the fair value of variable annuity assets.
Unobservable inputs used by management in determining fair value of embedded derivatives	The following table presents information about the unobservable inputs used by management in determining fair value of these Level 3 liabilities. See Note F — “ Derivatives .” Unobservable Input Range Adjustment for insurance subsidiary’s credit risk 1.9% – 3.6% over the risk-free rate Risk margin for uncertainty in cash flows 0.80% reduction in the discount rate Surrenders 4% – 21% of indexed account value Partial surrenders 2% – 9% of indexed account value Annuitizations 0.1% – 1% of indexed account value Deaths 1.9% – 10.6% of indexed account value Budgeted option costs 2.5% – 3.3% of indexed account value
Changes in balances of Level 3 financial assets	Changes in balances of Level 3 financial assets and liabilities carried at fair value during the first three months of 2020 and 2019 are presented below (in millions). The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. All transfers are reflected in the table at fair value as of the end of the reporting period. Total realized/unrealized gains (losses) included in Balance at December 31, 2019 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2020 AFS fixed maturities: U.S. government agency $ 15 $ 1 $ (1 ) $ — $ — $ — $ — $ 15 State and municipal 105 — 1 — (1 ) — — 105 Residential MBS 173 5 (12 ) — (5 ) 2 — 163 Commercial MBS 35 — — — (3 ) — — 32 Collateralized loan obligations 15 (7 ) 2 — — 158 — 168 Other asset-backed securities 1,286 (14 ) (11 ) 77 (178 ) 13 (143 ) 1,030 Corporate and other 1,758 (3 ) (27 ) 119 (36 ) 5 (268 ) 1,548 Total AFS fixed maturities 3,387 (18 ) (48 ) 196 (223 ) 178 (411 ) 3,061 Equity securities 437 (24 ) — 6 — 17 — 436 Assets of MIE 17 (1 ) — — — — — 16 Total Level 3 assets $ 3,841 $ (43 ) $ (48 ) $ 202 $ (223 ) $ 195 $ (411 ) $ 3,513 Embedded derivatives $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total Level 3 liabilities (*) $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2018 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2019 AFS fixed maturities: U.S. government agency $ 9 $ — $ — $ — $ (1 ) $ — $ — $ 8 State and municipal 59 — 5 — (1 ) — — 63 Residential MBS 197 5 (5 ) — (6 ) — (22 ) 169 Commercial MBS 56 — — — (1 ) — — 55 Collateralized loan obligations 116 — — — — — — 116 Other asset-backed securities 731 (3 ) 8 75 (114 ) — (143 ) 554 Corporate and other 1,996 2 31 432 (88 ) — (27 ) 2,346 Total AFS fixed maturities 3,164 4 39 507 (211 ) — (192 ) 3,311 Equity securities 336 1 — 1 — 16 — 354 Assets of MIE 21 (1 ) — — — — — 20 Total Level 3 assets $ 3,521 $ 4 $ 39 $ 508 $ (211 ) $ 16 $ (192 ) $ 3,685 Embedded derivatives $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) Total Level 3 liabilities (*) $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) (*) As previously discussed, these tables exclude the portion of MIE liabilities allocated to Level 3, which are derived from the fair value of the MIE assets.
Changes in balances of Level 3 financial liabilities	Changes in balances of Level 3 financial assets and liabilities carried at fair value during the first three months of 2020 and 2019 are presented below (in millions). The transfers into and out of Level 3 were due to changes in the availability of market observable inputs. All transfers are reflected in the table at fair value as of the end of the reporting period. Total realized/unrealized gains (losses) included in Balance at December 31, 2019 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2020 AFS fixed maturities: U.S. government agency $ 15 $ 1 $ (1 ) $ — $ — $ — $ — $ 15 State and municipal 105 — 1 — (1 ) — — 105 Residential MBS 173 5 (12 ) — (5 ) 2 — 163 Commercial MBS 35 — — — (3 ) — — 32 Collateralized loan obligations 15 (7 ) 2 — — 158 — 168 Other asset-backed securities 1,286 (14 ) (11 ) 77 (178 ) 13 (143 ) 1,030 Corporate and other 1,758 (3 ) (27 ) 119 (36 ) 5 (268 ) 1,548 Total AFS fixed maturities 3,387 (18 ) (48 ) 196 (223 ) 178 (411 ) 3,061 Equity securities 437 (24 ) — 6 — 17 — 436 Assets of MIE 17 (1 ) — — — — — 16 Total Level 3 assets $ 3,841 $ (43 ) $ (48 ) $ 202 $ (223 ) $ 195 $ (411 ) $ 3,513 Embedded derivatives $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total Level 3 liabilities (*) $ (3,730 ) $ 647 $ — $ (78 ) $ 62 $ — $ — $ (3,099 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2018 Net Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2019 AFS fixed maturities: U.S. government agency $ 9 $ — $ — $ — $ (1 ) $ — $ — $ 8 State and municipal 59 — 5 — (1 ) — — 63 Residential MBS 197 5 (5 ) — (6 ) — (22 ) 169 Commercial MBS 56 — — — (1 ) — — 55 Collateralized loan obligations 116 — — — — — — 116 Other asset-backed securities 731 (3 ) 8 75 (114 ) — (143 ) 554 Corporate and other 1,996 2 31 432 (88 ) — (27 ) 2,346 Total AFS fixed maturities 3,164 4 39 507 (211 ) — (192 ) 3,311 Equity securities 336 1 — 1 — 16 — 354 Assets of MIE 21 (1 ) — — — — — 20 Total Level 3 assets $ 3,521 $ 4 $ 39 $ 508 $ (211 ) $ 16 $ (192 ) $ 3,685 Embedded derivatives $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) Total Level 3 liabilities (*) $ (2,720 ) $ (462 ) $ — $ (112 ) $ 47 $ — $ — $ (3,247 ) (*) As previously discussed, these tables exclude the portion of MIE liabilities allocated to Level 3, which are derived from the fair value of the MIE assets.
Fair value of financial instruments	The carrying value and fair value of financial instruments that are not carried at fair value in the financial statements are summarized below (in millions): Carrying Fair Value Value Total Level 1 Level 2 Level 3 March 31, 2020 Financial assets: Cash and cash equivalents $ 1,673 $ 1,673 $ 1,673 $ — $ — Mortgage loans 1,346 1,350 — — 1,350 Policy loans 161 161 — — 161 Total financial assets not accounted for at fair value $ 3,180 $ 3,184 $ 1,673 $ — $ 1,511 Financial liabilities: Annuity benefits accumulated (*) $ 40,218 $ 39,773 $ — $ — $ 39,773 Long-term debt 1,473 1,411 — 1,408 3 Total financial liabilities not accounted for at fair value $ 41,691 $ 41,184 $ — $ 1,408 $ 39,776 December 31, 2019 Financial assets: Cash and cash equivalents $ 2,314 $ 2,314 $ 2,314 $ — $ — Mortgage loans 1,329 1,346 — — 1,346 Policy loans 164 164 — — 164 Total financial assets not accounted for at fair value $ 3,807 $ 3,824 $ 2,314 $ — $ 1,510 Financial liabilities: Annuity benefits accumulated (*) $ 40,159 $ 40,182 $ — $ — $ 40,182 Long-term debt 1,473 1,622 — 1,619 3 Total financial liabilities not accounted for at fair value $ 41,632 $ 41,804 $ — $ 1,619 $ 40,185 (*) Excludes $245 million and $247 million of life contingent annuities in the payout phase at March 31, 2020 and December 31, 2019 , respectively.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Available for sale fixed maturities	Available for sale fixed maturities at March 31, 2020 and December 31, 2019 , consisted of the following (in millions): Amortized Cost Allowance for Expected Credit Losses Gross Unrealized Net Unrealized Fair Value Gains Losses March 31, 2020 Fixed maturities: U.S. Government and government agencies $ 190 $ — $ 15 $ — $ 15 $ 205 States, municipalities and political subdivisions 6,526 — 388 (8 ) 380 6,906 Foreign government 164 — 6 — 6 170 Residential MBS 3,078 6 133 (74 ) 59 3,131 Commercial MBS 892 — 20 (5 ) 15 907 Collateralized loan obligations 4,456 17 5 (306 ) (301 ) 4,138 Other asset-backed securities 7,069 14 65 (362 ) (297 ) 6,758 Corporate and other 23,726 24 786 (569 ) 217 23,919 Total fixed maturities $ 46,101 $ 61 $ 1,418 $ (1,324 ) $ 94 $ 46,134 December 31, 2019 Fixed maturities: U.S. Government and government agencies $ 199 $ — $ 10 $ — $ 10 $ 209 States, municipalities and political subdivisions 6,604 — 363 (4 ) 359 6,963 Foreign government 170 — 3 (1 ) 2 172 Residential MBS 2,900 — 265 (5 ) 260 3,160 Commercial MBS 896 — 31 — 31 927 Collateralized loan obligations 4,307 — 10 (37 ) (27 ) 4,280 Other asset-backed securities 6,992 — 156 (20 ) 136 7,128 Corporate and other 22,456 — 1,231 (21 ) 1,210 23,666 Total fixed maturities $ 44,524 $ — $ 2,069 $ (88 ) $ 1,981 $ 46,505
Equity securities reported at fair value	Equity securities, which are reported at fair value with holding gains and losses recognized in net earnings, consisted of the following at March 31, 2020 and December 31, 2019 (in millions): March 31, 2020 December 31, 2019 Fair Value Fair Value Actual Cost over (under) Actual Cost over (under) Fair Value Cost Fair Value Cost Common stocks $ 1,315 $ 919 $ (396 ) $ 1,164 $ 1,283 $ 119 Perpetual preferred stocks 685 640 (45 ) 640 654 14 Total equity securities carried at fair value $ 2,000 $ 1,559 $ (441 ) $ 1,804 $ 1,937 $ 133
Available for sale securities in a continuous unrealized loss position	The following tables show gross unrealized losses (dollars in millions) on available for sale fixed maturities by investment category and length of time that individual securities have been in a continuous unrealized loss position at the following balance sheet dates. Less Than Twelve Months Twelve Months or More Unrealized Loss Fair Value Fair Value as % of Cost Unrealized Loss Fair Value Fair Value as % of Cost March 31, 2020 Fixed maturities: U.S. Government and government agencies $ — $ — — % $ — $ 1 100 % States, municipalities and political subdivisions (8 ) 235 97 % — 26 100 % Foreign government — 3 100 % — — — % Residential MBS (70 ) 1,562 96 % (4 ) 31 89 % Commercial MBS (5 ) 117 96 % — — — % Collateralized loan obligations (141 ) 2,234 94 % (165 ) 1,691 91 % Other asset-backed securities (352 ) 4,597 93 % (10 ) 94 90 % Corporate and other (554 ) 7,738 93 % (15 ) 98 87 % Total fixed maturities $ (1,130 ) $ 16,486 94 % $ (194 ) $ 1,941 91 % December 31, 2019 Fixed maturities: U.S. Government and government agencies $ — $ 16 100 % $ — $ 11 100 % States, municipalities and political subdivisions (3 ) 254 99 % (1 ) 82 99 % Foreign government (1 ) 70 99 % — — — % Residential MBS (4 ) 509 99 % (1 ) 69 99 % Commercial MBS — 17 100 % — — — % Collateralized loan obligations (11 ) 1,284 99 % (26 ) 1,728 99 % Other asset-backed securities (12 ) 1,211 99 % (8 ) 123 94 % Corporate and other (13 ) 1,100 99 % (8 ) 211 96 % Total fixed maturities $ (44 ) $ 4,461 99 % $ (44 ) $ 2,224 98 %
Roll forward of allowance for credit losses on fixed maturity securities	A progression of the allowance for expected credit losses on fixed maturity securities is shown below (in millions): 2020 Balance at January 1 $ — Impact of adoption of new accounting policy — Provision for expected credit losses 61 Reductions due to sales or redemptions — Balance at March 31 $ 61
Available for sale fixed maturity securities by contractual maturity date	The table below sets forth the scheduled maturities of available for sale fixed maturities as of March 31, 2020 (dollars in millions). Securities with sinking funds are reported at average maturity. Actual maturities may differ from contractual maturities because certain securities may be called or prepaid by the issuers. Amortized Fair Value Cost, net (*) Amount % Maturity One year or less $ 2,018 $ 2,027 4 % After one year through five years 10,563 10,710 23 % After five years through ten years 14,450 14,722 32 % After ten years 3,551 3,741 8 % 30,582 31,200 67 % Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years) 11,494 10,896 24 % MBS (average life of approximately 3-1/2 years) 3,964 4,038 9 % Total $ 46,040 $ 46,134 100 % (*) Amortized cost, net of allowance for expected credit losses.
Components of the net unrealized gain on securities, included in Accumulated Other Comprehensive Income	The following table shows (in millions) the components of the net unrealized gain on securities that is included in AOCI in AFG’s Balance Sheet. Pretax Deferred Tax Net March 31, 2020 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 124 $ (26 ) $ 98 Fixed maturities — all other (30 ) 7 (23 ) Total fixed maturities 94 (19 ) 75 Deferred policy acquisition costs — annuity segment (57 ) 12 (45 ) Annuity benefits accumulated (18 ) 3 (15 ) Unearned revenue 1 — 1 Total net unrealized gain on marketable securities $ 20 $ (4 ) $ 16 December 31, 2019 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 1,611 $ (338 ) $ 1,273 Fixed maturities — all other 370 (78 ) 292 Total fixed maturities 1,981 (416 ) 1,565 Deferred policy acquisition costs — annuity segment (681 ) 143 (538 ) Annuity benefits accumulated (219 ) 46 (173 ) Life, accident and health reserves (1 ) — (1 ) Unearned revenue 11 (2 ) 9 Total net unrealized gain on marketable securities $ 1,091 $ (229 ) $ 862 (*) Net unrealized gains on fixed maturity investments supporting AFG’s annuity benefits accumulated.
Net investment income earned and investment expenses incurred	The following table shows (in millions) investment income earned and investment expenses incurred. Three months ended March 31, 2020 2019 Investment income: Fixed maturities $ 491 $ 469 Equity securities: Dividends 17 22 Change in fair value (a) (b) (12 ) 11 Equity in earnings of partnerships and similar investments 25 21 Other 28 25 Gross investment income 549 548 Investment expenses (5 ) (6 ) Net investment income (b) $ 544 $ 542 (a) Although the change in the fair value of the majority of AFG’s equity securities is recorded in realized gains (losses) on securities, AFG records holding gains and losses in net investment income on equity securities classified as “trading” under previous guidance and on a small portfolio of limited partnership and similar investments that do not qualify for the equity method of accounting. (b) Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments	Realized gains (losses) and changes in unrealized appreciation (depreciation) included in AOCI related to fixed maturity and equity security investments are summarized as follows (in millions): Three months ended March 31, 2020 Three months ended March 31, 2019 Realized gains (losses) Realized gains (losses) Before Impairments Impairment Allowance Total Change in Unrealized Before Impairments Impairments Total Change in Unrealized Fixed maturities $ 29 $ (61 ) $ (32 ) $ (1,887 ) $ 3 $ (3 ) $ — $ 853 Equity securities (535 ) — (535 ) — 182 — 182 — Mortgage loans and other investments 4 — 4 — — — — — Other (*) (3 ) 15 12 816 1 1 2 (370 ) Total pretax (505 ) (46 ) (551 ) (1,071 ) 186 (2 ) 184 483 Tax effects 106 10 116 225 (39 ) — (39 ) (102 ) Net of tax $ (399 ) $ (36 ) $ (435 ) $ (846 ) $ 147 $ (2 ) $ 145 $ 381 (*) Primarily adjustments to deferred policy acquisition costs and reserves related to the annuity business.
Holding gains (losses) on equity securities still held	AFG recorded net holding gains (losses) on equity securities during the first three months of 2020 and 2019 on securities that were still owned at March 31, 2020 and March 31, 2019 as follows (in millions): Three months ended March 31, 2020 2019 Included in realized gains (losses) $ (540 ) $ 163 Included in net investment income (5 ) 11 $ (545 ) $ 174
Gross realized gains and losses on available for sale fixed maturity and equity security investments	Gross realized gains and losses (excluding impairment write-downs and mark-to-market of derivatives) on available for sale fixed maturity investment transactions consisted of the following (in millions): Three months ended March 31, 2020 2019 Gross gains $ 29 $ 6 Gross losses (4 ) (9 )

Derivatives (Tables)

Derivatives (Tables)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives included in Balance Sheet at fair value	The following derivatives that do not qualify for hedge accounting under GAAP are included in AFG’s Balance Sheet at fair value (in millions): March 31, 2020 December 31, 2019 Derivative Balance Sheet Line Asset Liability Asset Liability MBS with embedded derivatives Fixed maturities $ 103 $ — $ 102 $ — Fixed-indexed and variable-indexed annuities (embedded derivative) Annuity benefits accumulated — 3,099 — 3,730 Equity index call options Equity index call options 209 — 924 — Equity index put options Other liabilities — 8 — 1 Reinsurance contracts (embedded derivative) Other liabilities — 2 — 4 $ 312 $ 3,109 $ 1,026 $ 3,735
Summary of gain (loss) included in the Statement of Earnings for changes in the fair value of derivatives	The following table summarizes the gains (losses) included in AFG’s Statement of Earnings for changes in the fair value of derivatives that do not qualify for hedge accounting for the first three months of 2020 and 2019 (in millions): Three months ended March 31, Derivative Statement of Earnings Line 2020 2019 MBS with embedded derivatives Realized gains (losses) on securities $ 4 $ 6 Fixed-indexed and variable-indexed annuities (embedded derivative) Annuity benefits 647 (462 ) Equity index call options Annuity benefits (628 ) 366 Equity index put options Annuity benefits (6 ) 1 Reinsurance contract (embedded derivative) Net investment income 2 (1 ) $ 19 $ (90 )

Deferred Policy Acquisition C_2

Deferred Policy Acquisition Costs (Tables)	3 Months Ended
	Mar. 31, 2020
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Costs Details	A progression of deferred policy acquisition costs is presented below (in millions): P&C Annuity and Other Deferred Deferred Sales Consolidated Costs Costs Inducements PVFP Subtotal Unrealized (*) Total Total Balance at December 31, 2019 $ 322 $ 1,303 $ 75 $ 36 $ 1,414 $ (699 ) $ 715 $ 1,037 Additions 158 49 1 — 50 — 50 208 Amortization: Periodic amortization (170 ) (98 ) (3 ) (2 ) (103 ) — (103 ) (273 ) Included in realized gains — 10 — — 10 — 10 10 Foreign currency translation — — — — — — — — Change in unrealized — — — — — 591 591 591 Balance at March 31, 2020 $ 310 $ 1,264 $ 73 $ 34 $ 1,371 $ (108 ) $ 1,263 $ 1,573 Balance at December 31, 2018 $ 299 $ 1,285 $ 86 $ 42 $ 1,413 $ (30 ) $ 1,383 $ 1,682 Additions 187 64 1 — 65 — 65 252 Amortization: Periodic amortization (175 ) (15 ) (3 ) (2 ) (20 ) — (20 ) (195 ) Included in realized gains — 2 — — 2 — 2 2 Foreign currency translation 1 — — — — — — 1 Change in unrealized — — — — — (295 ) (295 ) (295 ) Balance at March 31, 2019 $ 312 $ 1,336 $ 84 $ 40 $ 1,460 $ (325 ) $ 1,135 $ 1,447 (*) Adjustments to DPAC related to net unrealized gains/losses on securities and cash flow hedges.

Managed Investment Entities (Ta

Managed Investment Entities (Tables)	3 Months Ended
	Mar. 31, 2020
Variable Interest Entity, Primary Beneficiary, Does Not Hold Majority Voting Interest, Disclosures [Abstract]
Selected financial information related to collateralized loan obligations	Selected financial information related to the CLOs is shown below (in millions): Three months ended March 31, 2020 2019 Investment in CLO tranches at end of period $ 161 $ 193 Gains (losses) on change in fair value of assets/liabilities (a): Assets (679 ) 87 Liabilities 636 (87 ) Management fees paid to AFG 4 3 CLO earnings (losses) attributable to AFG shareholders (b) (36 ) 11 (a) Included in revenues in AFG’s Statement of Earnings. (b) Included in earnings before income taxes in AFG’s Statement of Earnings.

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	Long-term debt consisted of the following (in millions): March 31, 2020 December 31, 2019 Principal Discount and Issue Costs Carrying Value Principal Discount and Issue Costs Carrying Value Direct Senior Obligations of AFG: 4.50% Senior Notes due June 2047 $ 590 $ (2 ) $ 588 $ 590 $ (2 ) $ 588 3.50% Senior Notes due August 2026 425 (3 ) 422 425 (3 ) 422 Other 3 — 3 3 — 3 1,018 (5 ) 1,013 1,018 (5 ) 1,013 Direct Subordinated Obligations of AFG: 5.125% Subordinate Debentures due December 2059 200 (6 ) 194 200 (6 ) 194 6% Subordinated Debentures due November 2055 150 (5 ) 145 150 (5 ) 145 5.875% Subordinated Debentures due March 2059 125 (4 ) 121 125 (4 ) 121 475 (15 ) 460 475 (15 ) 460 $ 1,493 $ (20 ) $ 1,473 $ 1,493 $ (20 ) $ 1,473

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Components of accumulated other comprehensive income (loss)	The progression of the components of accumulated other comprehensive income follows (in millions): Other Comprehensive Income (Loss) AOCI Beginning Balance Pretax Tax Net of tax Attributable to noncontrolling interests Attributable to shareholders AOCI Ending Balance Three months ended March 31, 2020 Net unrealized gains (losses) on securities: Unrealized holding losses on securities arising during the period $ (1,095 ) $ 230 $ (865 ) $ — $ (865 ) Reclassification adjustment for realized (gains) losses included in net earnings (*) 24 (5 ) 19 — 19 Total net unrealized gains (losses) on securities $ 862 (1,071 ) 225 (846 ) — (846 ) $ 16 Net unrealized gains on cash flow hedges 17 34 (7 ) 27 — 27 44 Foreign currency translation adjustments (9 ) (10 ) — (10 ) (2 ) (12 ) (21 ) Pension and other postretirement plans adjustments (7 ) — — — — — (7 ) Total $ 863 $ (1,047 ) $ 218 $ (829 ) $ (2 ) $ (831 ) $ 32 Three months ended March 31, 2019 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 487 $ (103 ) $ 384 $ — $ 384 Reclassification adjustment for realized (gains) losses included in net earnings (*) (4 ) 1 (3 ) — (3 ) Total net unrealized gains on securities $ 83 483 (102 ) 381 — 381 $ 464 Net unrealized gains (losses) on cash flow hedges (11 ) 14 (3 ) 11 — 11 — Foreign currency translation adjustments (16 ) 4 — 4 — 4 (12 ) Pension and other postretirement plans adjustments (8 ) — — — — — (8 ) Total $ 48 $ 501 $ (105 ) $ 396 $ — $ 396 $ 444 (*) The reclassification adjustment out of net unrealized gains (losses) on securities affected the following lines in AFG’s Statement of Earnings: OCI component Affected line in the statement of earnings Pretax Realized gains (losses) on securities Tax Provision (credit) for income taxes

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Reconciliation of income taxes at the statutory rate and income taxes shown in the Statement of Earnings	The following is a reconciliation of income taxes at the statutory rate of 21% to the provision for income taxes as shown in AFG’s Statement of Earnings (dollars in millions): Three months ended March 31, 2020 2019 Amount % of EBT Amount % of EBT Earnings (loss) before income taxes (“EBT”) $ (388 ) $ 413 Income taxes at statutory rate $ (81 ) 21 % $ 87 21 % Effect of: Stock-based compensation (4 ) 1 % (2 ) — % Tax exempt interest (3 ) 1 % (4 ) (1 %) Dividends received deduction (1 ) — % (1 ) — % Nondeductible expenses 2 (1 %) 2 — % Change in valuation allowance 2 (1 %) 2 — % Foreign operations 1 — % — — % Other — 1 % 3 1 % Provision (credit) for income taxes as shown in the statement of earnings $ (84 ) 22 % $ 87 21 %

Insurance (Tables)

Insurance (Tables)	3 Months Ended
	Mar. 31, 2020
Insurance [Abstract]
Reconciliation of beginning and ending liability for unpaid losses and loss adjustment expenses	The following table provides an analysis of changes in the liability for losses and loss adjustment expenses during the first three months of 2020 and 2019 (in millions): Three months ended March 31, 2020 2019 Balance at beginning of year $ 10,232 $ 9,741 Less reinsurance recoverables, net of allowance 3,024 2,942 Net liability at beginning of year 7,208 6,799 Provision for losses and LAE occurring in the current period 749 737 Net increase (decrease) in the provision for claims of prior years (42 ) (45 ) Total losses and LAE incurred (*) 707 692 Payments for losses and LAE of: Current year (75 ) (89 ) Prior years (676 ) (615 ) Total payments (751 ) (704 ) Foreign currency translation and other (22 ) 1 Net liability at end of period 7,142 6,788 Add back reinsurance recoverables, net of allowance 2,964 2,835 Gross unpaid losses and LAE included in the balance sheet at end of period $ 10,106 $ 9,623 (*) Includes $40 million in losses and LAE incurred in the Neon exited lines in the first three months of 2020 .
Reinsurance Recoverable and Premiums Receivable, Allowance for Credit Loss	Progressions of the 2020 allowance for expected credit losses are shown below (in millions): Recoverables from Reinsurers Premiums Receivable Balance at January 1 $ 18 $ 13 Impact of adoption of new accounting policy (6 ) (3 ) Provision (credit) for expected credit losses 1 (1 ) Write-offs charged against the allowance — — Balance at March 31 $ 13 $ 9

Accounting Policies - Narrative

Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change	$ 5,047	$ 5,665		$ 6,269	$ 4,972
Operating lease liability	182			180
Operating lease right-of-use asset	$ 162			158
Weighted average common shares adjustment related to stock-based compensation (shares)	0	1,300,000
Anti-dilutive potential common shares related to stock-based compensation plans (shares)	800,000	0
Maturities of short term investments	3 months
Retained Earnings
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change	$ 3,616	$ 3,875		$ 4,009	$ 3,588
Cumulative effect adjustment in period of adoption | Retained Earnings | Accounting Standards Update 2016-13
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change	$ 7		$ 7

Acquisition of Business - Narra

Acquisition of Business - Narrative (Details) - Atlas Financial Holdings - Paratransit Business - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Jun. 10, 2019
Business Acquisition [Line Items]
Gross written premiums eligible for renewal	$ 110
Business acquisition, price as a percent of gross written premiums		15.00%
Warrant term to acquire shares		5 years
Number of shares able to be acquired with the warrant		2.4
Business acquisition, percentage of entity acquired by warrants		19.90%
Equity securities | Public company warrants
Business Acquisition [Line Items]
Fair value of warrant on date received		$ 1

Segments of Operations - Narrat

Segments of Operations - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)segment		Mar. 31, 2019USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment	3
Total premiums earned	$ 1,209		$ 1,173
Net investment income	544	[1]	542
Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	1,209		1,173
Net investment income	93	[2]	104
Property and casualty insurance underwriting	87		87
Investment and other income, net	84	[3]	95
Other lines | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	71	[4]	0
Property and casualty insurance underwriting	(2)	[5]	(1)
Neon Capital Limited
Segment Reporting Information [Line Items]
Net investment income	(6)
Neon Capital Limited | Other lines | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned			88
Net investment income	(6)
Property and casualty insurance underwriting	(1)		$ 10
Investment and other income, net	$ (9)
[1]	Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.
[2]	Includes a net loss of $6 million in the Neon exited lines, primarily from the change in fair value of equity securities.
[3]	Includes $9 million
[4]	Represents premiums earned in the Neon exited lines during the first three months of 2020. Neon’s $88 million in earned premiums during the first three months of 2019 are included in the Specialty casualty sub-segment.
[5]	Includes a $1 million underwriting loss in the first three months of 2020 in the Neon exited lines. Neon’s $10 million underwriting loss in the first three months of 2019 is included in the Specialty casualty sub-segment.

Segments of Operations - Revenu

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Segment Reporting Information [Line Items]
Total premiums earned	$ 1,209		$ 1,173
Net investment income	544	[1]	542
Other income	57		56
Revenues before realized gains (losses)	1,826		1,840
Realized gains (losses) on securities	(551)		184
Total revenues	1,275		2,024
Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	1,209		1,173
Net investment income	93	[2]	104
Other income	5		3
Revenues before realized gains (losses)	1,307		1,280
Annuity
Segment Reporting Information [Line Items]
Net investment income	422		435
Other income	35		28
Revenues before realized gains (losses)	457		463
Other
Segment Reporting Information [Line Items]
Revenues before realized gains (losses)	62		97
Specialty Property and transportation | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	386		361
Specialty casualty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	556		629
Specialty financial | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	156		146
Other specialty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	40		37
Other lines | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned	$ 71	[3]	$ 0
[1]	Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.
[2]	Includes a net loss of $6 million in the Neon exited lines, primarily from the change in fair value of equity securities.
[3]	Represents premiums earned in the Neon exited lines during the first three months of 2020. Neon’s $88 million in earned premiums during the first three months of 2019 are included in the Specialty casualty sub-segment.

Segments of Operations - Earnin

Segments of Operations - Earnings before income taxes by segment and sub-segment (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020		Mar. 31, 2019
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes		$ 163		$ 229
Realized gains (losses) on securities		(551)		184
Earnings (loss) before income taxes		(388)		413
Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		87		87
Investment and other income, net		84	[1]	95
Earnings before realized gains (losses) and income taxes		171		182
Annuity
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes		29		90
Other
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes	[2]	(37)		(43)
Specialty Property and transportation | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		27		39
Specialty casualty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		52		36
Specialty financial | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		17		13
Other specialty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		(7)		0
Other lines | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		$ (2)	[3]	$ (1)
[1]	Includes $9 million
[2]	Includes holding company interest and expenses.
[3]	Includes a $1 million underwriting loss in the first three months of 2020 in the Neon exited lines. Neon’s $10 million underwriting loss in the first three months of 2019 is included in the Specialty casualty sub-segment.

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)basispointprofessionalsecurity	Dec. 31, 2019USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
AFG's internal investment professionals | professional	20
Level 3 assets as a percentage of total assets measured at fair value	7.00%
Percentage of level 3 assets that were priced using non-binding broker quotes	43.00%
Level 3 assets that were priced using non-binding broker quotes | $	$ 1,520
Percent of spreads between 200 and 700 basis points	70.00%
Life contingent annuities | $	$ 245	$ 247
Fixed-indexed and variable-indexed annuities (embedded derivative), majority of future years | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable input surrenders used in Level 3 fair value determination	7.00%
Fixed-indexed and variable-indexed annuities (embedded derivative), majority of future years | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable input surrenders used in Level 3 fair value determination	10.00%
Fixed-indexed and variable-indexed annuities (embedded derivative)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of derivatives in annuity benefits accumulated measured using a discounted cash flow approach | $	$ 3,100
Fixed-indexed and variable-indexed annuities (embedded derivative) | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable input surrenders used in Level 3 fair value determination	4.00%
Fixed-indexed and variable-indexed annuities (embedded derivative) | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unobservable input surrenders used in Level 3 fair value determination	21.00%
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Internally developed level 3 assets | $	$ 1,630
Third party pricing model | Fixed maturities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Internally developed level 3 assets | $	$ 727
Securities priced using a third-party model | security	37
Basis points credit spread applied by management using third party model | basispoint	414
Third party pricing model | Fixed maturities | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Basis points credit spread applied by management using third party model | basispoint	200
Third party pricing model | Fixed maturities | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Basis points credit spread applied by management using third party model | basispoint	700
Credit spread used in pricing model | Third party pricing model | Fixed maturities | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Basis points credit spread applied by management using third party model | basispoint	53
Credit spread used in pricing model | Third party pricing model | Fixed maturities | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Basis points credit spread applied by management using third party model | basispoint	1,253

Fair Value Measurements - Asset

Fair Value Measurements - Assets and liabilities measured and carried at fair value in the financial statements (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Assets:
Available for sale (AFS) fixed maturities		$ 46,134	$ 46,505
Trading fixed maturities		96	113
Equity securities		1,559	1,937
Equity index call options		209	924
Assets of managed investment entities (“MIE”)		4,026	4,736
Variable annuity assets (separate accounts)	[1]	497	628
Total assets accounted for at fair value		52,646	54,893
Liabilities:
Liabilities of managed investment entities		3,865	4,571
Total liabilities accounted for at fair value		6,974	8,311
Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		3,099	3,730
Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		10	10
Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		46,134	46,505
Trading fixed maturities		96	113
U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		205	209
States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		6,906	6,963
Foreign government
Assets:
Available for sale (AFS) fixed maturities		170	172
Residential MBS
Assets:
Available for sale (AFS) fixed maturities		3,131	3,160
Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		907	927
Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities		4,138	4,280
Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities		6,758	7,128
Corporate and other
Assets:
Available for sale (AFS) fixed maturities		23,919	23,666
Equity securities
Assets:
Equity securities		1,559	1,937
Other assets
Assets:
Equity index call options		125	50
Level 1
Assets:
Assets of managed investment entities (“MIE”)		169	213
Variable annuity assets (separate accounts)	[1]	0	0
Total assets accounted for at fair value		1,409	1,828
Liabilities:
Liabilities of managed investment entities		162	206
Total liabilities accounted for at fair value		162	206
Level 1 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 1 | Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 1 | Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		183	180
Trading fixed maturities		1	2
Level 1 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		158	151
Level 1 | States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Foreign government
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Residential MBS
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		25	29
Level 1 | Equity securities
Assets:
Equity securities		1,056	1,433
Level 1 | Other assets
Assets:
Equity index call options		0	0
Level 2
Assets:
Assets of managed investment entities (“MIE”)		3,841	4,506
Variable annuity assets (separate accounts)	[1]	497	628
Total assets accounted for at fair value		47,724	49,224
Liabilities:
Liabilities of managed investment entities		3,688	4,349
Total liabilities accounted for at fair value		3,698	4,359
Level 2 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 2 | Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		10	10
Level 2 | Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		42,890	42,938
Trading fixed maturities		95	111
Level 2 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		32	43
Level 2 | States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		6,801	6,858
Level 2 | Foreign government
Assets:
Available for sale (AFS) fixed maturities		170	172
Level 2 | Residential MBS
Assets:
Available for sale (AFS) fixed maturities		2,968	2,987
Level 2 | Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		875	892
Level 2 | Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities		3,970	4,265
Level 2 | Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities		5,728	5,842
Level 2 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		22,346	21,879
Level 2 | Equity securities
Assets:
Equity securities		67	67
Level 2 | Other assets
Assets:
Equity index call options		125	50
Level 3
Assets:
Assets of managed investment entities (“MIE”)		16	17
Variable annuity assets (separate accounts)	[1]	0	0
Total assets accounted for at fair value		3,513	3,841
Liabilities:
Liabilities of managed investment entities		15	16
Total liabilities accounted for at fair value		3,114	3,746
Level 3 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		3,099	3,730
Level 3 | Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 3 | Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		3,061	3,387
Trading fixed maturities		0	0
Level 3 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		15	15
Level 3 | States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		105	105
Level 3 | Foreign government
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 3 | Residential MBS
Assets:
Available for sale (AFS) fixed maturities		163	173
Level 3 | Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		32	35
Level 3 | Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities		168	15
Level 3 | Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities		1,030	1,286
Level 3 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		1,548	1,758
Level 3 | Equity securities
Assets:
Equity securities		436	437
Level 3 | Other assets
Assets:
Equity index call options		0	0
Equity index call options | Equity index call options
Assets:
Equity index call options		209	924
Equity index call options | Level 1 | Equity index call options
Assets:
Equity index call options		0	0
Equity index call options | Level 2 | Equity index call options
Assets:
Equity index call options		209	924
Equity index call options | Level 3 | Equity index call options
Assets:
Equity index call options		$ 0	$ 0
[1]	Variable annuity liabilities equal the fair value of variable annuity assets.

Fair Value Measurements - Unobs

Fair Value Measurements - Unobservable inputs used in determining fair value of embedded derivatives (Details) - Embedded derivatives	3 Months Ended
	Mar. 31, 2020
Unobservable inputs used by management in determining fair value of embedded derivatives
Risk margin for uncertainty in cash flows	0.80%
Minimum
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary’s credit risk	1.90%
Surrenders	4.00%
Partial surrenders	2.00%
Annuitizations	0.10%
Deaths	1.90%
Budgeted option costs	2.50%
Maximum
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary’s credit risk	3.60%
Surrenders	21.00%
Partial surrenders	9.00%
Annuitizations	1.00%
Deaths	10.60%
Budgeted option costs	3.30%

Fair Value Measurements - Chang

Fair Value Measurements - Changes in balances of Level 3 financial assets carried at fair value (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	$ 3,841	$ 3,521
Total realized/unrealized gains (losses) included in Net income	(43)	4
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(48)	39
Purchases and issuances	202	508
Sales and settlements	(223)	(211)
Transfer into Level 3	195	16
Transfer out of Level 3	(411)	(192)
Financial assets, Ending Balance	3,513	3,685
Fixed maturities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	3,387	3,164
Total realized/unrealized gains (losses) included in Net income	(18)	4
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(48)	39
Purchases and issuances	196	507
Sales and settlements	(223)	(211)
Transfer into Level 3	178	0
Transfer out of Level 3	(411)	(192)
Financial assets, Ending Balance	3,061	3,311
U.S. government agency
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	15	9
Total realized/unrealized gains (losses) included in Net income	1	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(1)	0
Purchases and issuances	0	0
Sales and settlements	0	(1)
Transfer into Level 3	0	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	15	8
State and municipal
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	105	59
Total realized/unrealized gains (losses) included in Net income	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	1	5
Purchases and issuances	0	0
Sales and settlements	(1)	(1)
Transfer into Level 3	0	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	105	63
Residential MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	173	197
Total realized/unrealized gains (losses) included in Net income	5	5
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(12)	(5)
Purchases and issuances	0	0
Sales and settlements	(5)	(6)
Transfer into Level 3	2	0
Transfer out of Level 3	0	(22)
Financial assets, Ending Balance	163	169
Commercial MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	35	56
Total realized/unrealized gains (losses) included in Net income	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases and issuances	0	0
Sales and settlements	(3)	(1)
Transfer into Level 3	0	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	32	55
Collateralized loan obligations
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	15	116
Total realized/unrealized gains (losses) included in Net income	(7)	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	2	0
Purchases and issuances	0	0
Sales and settlements	0	0
Transfer into Level 3	158	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	168	116
Other asset-backed securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	1,286	731
Total realized/unrealized gains (losses) included in Net income	(14)	(3)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(11)	8
Purchases and issuances	77	75
Sales and settlements	(178)	(114)
Transfer into Level 3	13	0
Transfer out of Level 3	(143)	(143)
Financial assets, Ending Balance	1,030	554
Corporate and other
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	1,758	1,996
Total realized/unrealized gains (losses) included in Net income	(3)	2
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	(27)	31
Purchases and issuances	119	432
Sales and settlements	(36)	(88)
Transfer into Level 3	5	0
Transfer out of Level 3	(268)	(27)
Financial assets, Ending Balance	1,548	2,346
Equity securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	437	336
Total realized/unrealized gains (losses) included in Net income	(24)	1
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases and issuances	6	1
Sales and settlements	0	0
Transfer into Level 3	17	16
Transfer out of Level 3	0	0
Financial assets, Ending Balance	436	354
Assets of MIE
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	17	21
Total realized/unrealized gains (losses) included in Net income	(1)	(1)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases and issuances	0	0
Sales and settlements	0	0
Transfer into Level 3	0	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	$ 16	$ 20

Fair Value Measurements - Cha_2

Fair Value Measurements - Changes in balances of Level 3 financial liabilities carried at fair value (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		$ (3,730)	$ (2,720)
Total realized/unrealized gains (losses) included in Net income		647	(462)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0
Purchases and issuances		(78)	(112)
Sales and settlements		62	47
Transfer into Level 3		0	0
Transfer out of Level 3		0	0
Financial liabilities, Ending Balance	[1]	(3,099)	(3,247)
Embedded derivatives
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		(3,730)	(2,720)
Total realized/unrealized gains (losses) included in Net income		647	(462)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0
Purchases and issuances		(78)	(112)
Sales and settlements		62	47
Transfer into Level 3		0	0
Transfer out of Level 3		0	0
Financial liabilities, Ending Balance		$ (3,099)	$ (3,247)
[1]	As previously discussed, these tables exclude the portion of MIE liabilities allocated to Level 3, which are derived from the fair value of the MIE assets.

Fair Value Measurements - The c

Fair Value Measurements - The carrying value and fair value of financial instruments (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Financial assets:
Mortgage loans		$ 1,346	$ 1,329
Policy loans		161	164
Financial liabilities:
Long-term debt		1,473	1,473
Level 1
Financial assets:
Cash and cash equivalents		1,673	2,314
Mortgage loans		0	0
Policy loans		0	0
Total financial assets not accounted for at fair value		1,673	2,314
Financial liabilities:
Annuity benefits accumulated	[1]	0	0
Long-term debt		0	0
Total financial liabilities not accounted for at fair value		0	0
Level 2
Financial assets:
Cash and cash equivalents		0	0
Mortgage loans		0	0
Policy loans		0	0
Total financial assets not accounted for at fair value		0	0
Financial liabilities:
Annuity benefits accumulated	[1]	0	0
Long-term debt		1,408	1,619
Total financial liabilities not accounted for at fair value		1,408	1,619
Level 3
Financial assets:
Cash and cash equivalents		0	0
Mortgage loans		1,350	1,346
Policy loans		161	164
Total financial assets not accounted for at fair value		1,511	1,510
Financial liabilities:
Annuity benefits accumulated	[1]	39,773	40,182
Long-term debt		3	3
Total financial liabilities not accounted for at fair value		39,776	40,185
Carrying Value
Financial assets:
Cash and cash equivalents		1,673	2,314
Mortgage loans		1,346	1,329
Policy loans		161	164
Total financial assets not accounted for at fair value		3,180	3,807
Financial liabilities:
Annuity benefits accumulated	[1]	40,218	40,159
Long-term debt		1,473	1,473
Total financial liabilities not accounted for at fair value		41,691	41,632
Fair Value
Financial assets:
Cash and cash equivalents		1,673	2,314
Mortgage loans		1,350	1,346
Policy loans		161	164
Total financial assets not accounted for at fair value		3,184	3,824
Financial liabilities:
Annuity benefits accumulated	[1]	39,773	40,182
Long-term debt		1,411	1,622
Total financial liabilities not accounted for at fair value		$ 41,184	$ 41,804
[1]	Excludes $245 million and $247 million of life contingent annuities in the payout phase at March 31, 2020 and December 31, 2019 , respectively.

Investments - Narrative (Detail

Investments - Narrative (Details) $ in Millions		3 Months Ended
		Mar. 31, 2020USD ($)security		Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Schedule of Investments [Line Items]
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade		83.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade		89.00%
Allowance for credit losses		$ 61
Net investment income		544	[1]	$ 542
Investment income		549		548
Fixed maturities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities		$ (1,324)			$ (88)
Number of available for sale securities in an unrealized loss position | security		1,871
Residential MBS
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities		$ (74)			(5)
Allowance for credit losses		6
Collateralized loan obligations
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities		(306)			(37)
Allowance for credit losses		17
Corporate bonds
Schedule of Investments [Line Items]
Allowance for credit losses		24
Other asset-backed securities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities		(362)			$ (20)
Allowance for credit losses		14
Neon Capital Limited
Schedule of Investments [Line Items]
Net investment income		(6)
Accounting Standards Update 2016-01 | Equity securities
Schedule of Investments [Line Items]
Investment income	[2]	(12)	[1]	$ 11
Accounting Standards Update 2016-01 | Equity securities | Neon Capital Limited
Schedule of Investments [Line Items]
Investment income	[2]	$ (7)
[1]	Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.
[2]	Although the change in the fair value of the majority of AFG’s equity securities is recorded in realized gains (losses) on securities, AFG records holding gains and losses in net investment income on equity securities classified as “trading” under previous guidance and on a small portfolio of limited partnership and similar investments that do not qualify for the equity method of accounting.

Investments - Available for sal

Investments - Available for sale fixed maturities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	$ 46,101	$ 44,524
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(61)	0
Available for sale (AFS) fixed maturities	46,134	46,505
Total fixed maturities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	46,101	44,524
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(61)	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	1,418	2,069
Fixed maturities, Available for sale, Gross Unrealized, Losses	(1,324)	(88)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	94	1,981
Available for sale (AFS) fixed maturities	46,134	46,505
U.S. Government and government agencies
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	190	199
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	0	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	15	10
Fixed maturities, Available for sale, Gross Unrealized, Losses	0	0
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	15	10
Available for sale (AFS) fixed maturities	205	209
States, municipalities and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	6,526	6,604
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	0	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	388	363
Fixed maturities, Available for sale, Gross Unrealized, Losses	(8)	(4)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	380	359
Available for sale (AFS) fixed maturities	6,906	6,963
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	164	170
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	0	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	6	3
Fixed maturities, Available for sale, Gross Unrealized, Losses	0	(1)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	6	2
Available for sale (AFS) fixed maturities	170	172
Residential MBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	3,078	2,900
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(6)	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	133	265
Fixed maturities, Available for sale, Gross Unrealized, Losses	(74)	(5)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	59	260
Available for sale (AFS) fixed maturities	3,131	3,160
Commercial MBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	892	896
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	0	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	20	31
Fixed maturities, Available for sale, Gross Unrealized, Losses	(5)	0
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	15	31
Available for sale (AFS) fixed maturities	907	927
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	4,456	4,307
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(17)	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	5	10
Fixed maturities, Available for sale, Gross Unrealized, Losses	(306)	(37)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	(301)	(27)
Other asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	7,069	6,992
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(14)	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	65	156
Fixed maturities, Available for sale, Gross Unrealized, Losses	(362)	(20)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	(297)	136
Available for sale (AFS) fixed maturities	6,758	7,128
Corporate and other
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, Available for sale, Amortized Cost	23,726	22,456
Fixed maturities, Available for Sale, Allowance for Expected Credit Losses	(24)	0
Fixed maturities, Available for sale, Gross Unrealized, Gains	786	1,231
Fixed maturities, Available for sale, Gross Unrealized, Losses	(569)	(21)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	217	1,210
Available for sale (AFS) fixed maturities	23,919	23,666
Managed by third parties | Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Available for sale (AFS) fixed maturities	$ 4,138	$ 4,280

Investments - Equity securities

Investments - Equity securities reported at fair value (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt and Equity Securities, FV-NI [Line Items]
Equity securities	$ 1,559	$ 1,937
Common stocks
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at cost	1,315	1,164
Equity securities	919	1,283
Equity securities, fair value in excess of cost	(396)	119
Perpetual preferred stocks
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at cost	685	640
Equity securities	640	654
Equity securities, fair value in excess of cost	(45)	14
Equity securities
Debt and Equity Securities, FV-NI [Line Items]
Equity securities, at cost	2,000	1,804
Equity securities	1,559	1,937
Equity securities, fair value in excess of cost	$ (441)	$ 133

Investments - Gross unrealized

Investments - Gross unrealized losses on securities by investment category and length of time that have been in a continuous unrealized loss position (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Total fixed maturities
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (1,130)	$ (44)
Fair Value - Less than twelve months	$ 16,486	$ 4,461
Fair Value as % of Cost - Less than twelve months	94.00%	99.00%
Unrealized Loss - Twelve months or more	$ (194)	$ (44)
Fair Value - Twelve months or more	$ 1,941	$ 2,224
Fair Value as % of Cost - Twelve months or more	91.00%	98.00%
U.S. Government and government agencies
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ 0	$ 0
Fair Value - Less than twelve months	$ 0	$ 16
Fair Value as % of Cost - Less than twelve months	0.00%	100.00%
Unrealized Loss - Twelve months or more	$ 0	$ 0
Fair Value - Twelve months or more	$ 1	$ 11
Fair Value as % of Cost - Twelve months or more	100.00%	100.00%
States, municipalities and political subdivisions
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (8)	$ (3)
Fair Value - Less than twelve months	$ 235	$ 254
Fair Value as % of Cost - Less than twelve months	97.00%	99.00%
Unrealized Loss - Twelve months or more	$ 0	$ (1)
Fair Value - Twelve months or more	$ 26	$ 82
Fair Value as % of Cost - Twelve months or more	100.00%	99.00%
Foreign government
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ 0	$ (1)
Fair Value - Less than twelve months	$ 3	$ 70
Fair Value as % of Cost - Less than twelve months	100.00%	99.00%
Unrealized Loss - Twelve months or more	$ 0	$ 0
Fair Value - Twelve months or more	$ 0	$ 0
Fair Value as % of Cost - Twelve months or more	0.00%	0.00%
Residential MBS
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (70)	$ (4)
Fair Value - Less than twelve months	$ 1,562	$ 509
Fair Value as % of Cost - Less than twelve months	96.00%	99.00%
Unrealized Loss - Twelve months or more	$ (4)	$ (1)
Fair Value - Twelve months or more	$ 31	$ 69
Fair Value as % of Cost - Twelve months or more	89.00%	99.00%
Commercial MBS
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (5)	$ 0
Fair Value - Less than twelve months	$ 117	$ 17
Fair Value as % of Cost - Less than twelve months	96.00%	100.00%
Unrealized Loss - Twelve months or more	$ 0	$ 0
Fair Value - Twelve months or more	$ 0	$ 0
Fair Value as % of Cost - Twelve months or more	0.00%	0.00%
Collateralized loan obligations
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (141)	$ (11)
Fair Value - Less than twelve months	$ 2,234	$ 1,284
Fair Value as % of Cost - Less than twelve months	94.00%	99.00%
Unrealized Loss - Twelve months or more	$ (165)	$ (26)
Fair Value - Twelve months or more	$ 1,691	$ 1,728
Fair Value as % of Cost - Twelve months or more	91.00%	99.00%
Other asset-backed securities
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (352)	$ (12)
Fair Value - Less than twelve months	$ 4,597	$ 1,211
Fair Value as % of Cost - Less than twelve months	93.00%	99.00%
Unrealized Loss - Twelve months or more	$ (10)	$ (8)
Fair Value - Twelve months or more	$ 94	$ 123
Fair Value as % of Cost - Twelve months or more	90.00%	94.00%
Corporate and other
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (554)	$ (13)
Fair Value - Less than twelve months	$ 7,738	$ 1,100
Fair Value as % of Cost - Less than twelve months	93.00%	99.00%
Unrealized Loss - Twelve months or more	$ (15)	$ (8)
Fair Value - Twelve months or more	$ 98	$ 211
Fair Value as % of Cost - Twelve months or more	87.00%	96.00%

Investments - Allowance for cre

Investments - Allowance for credit losses on fixed maturities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 0
Impact of adoption of new accounting policy	61
Provision for expected credit losses	61
Reductions due to sales or redemptions	0
Ending balance	61
Accounting Standards Update 2016-13
Allowance for Credit Losses [Roll Forward]
Impact of adoption of new accounting policy	0
Ending balance	$ 0

Investments - Scheduled maturit

Investments - Scheduled maturities of available for sale fixed maturities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Fair Value Percent, Fiscal Year Maturity [Abstract]
Average life of ABS	4 years 6 months
Average life of MBS	3 years 6 months
Fixed maturities
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
One year or less	$ 2,018	[1]
After one year through five years	10,563	[1]
After five years through ten years	14,450	[1]
After ten years	3,551	[1]
Fixed maturities amortized cost, Subtotal	30,582	[1]
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years)	11,494	[1]
MBS (average life of approximately 3-1/2 years)	3,964	[1]
Amortized Cost	46,040	[1]
Fair Value, Fiscal Year Maturity [Abstract]
One year or less	2,027
After one year through five years	10,710
After five years through ten years	14,722
After ten years	3,741
Fixed maturities fair value, Subtotal	31,200
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years)	10,896
MBS (average life of approximately 3-1/2 years)	4,038
Fair Value	$ 46,134
Fair Value Percent, Fiscal Year Maturity [Abstract]
One year or less	4.00%
After one year through five years	23.00%
After five years through ten years	32.00%
After ten years	8.00%
Fixed maturities fair value, Subtotal, Percent	67.00%
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years)	24.00%
MBS (average life of approximately 3-1/2 years)	9.00%
Fair value, Total, Percent	100.00%
[1]	Amortized cost, net of allowance for expected credit losses.

Investments - Components of the

Investments - Components of the net unrealized gain on securities that is included in AOCI in the Balance Sheet (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Unrealized gain on:
Pretax		$ 20	$ 1,091
Deferred Tax		(4)	(229)
Net		16	862
Total fixed maturities
Unrealized gain on:
Pretax		94	1,981
Deferred Tax		(19)	(416)
Net		75	1,565
Fixed maturities — annuity segment
Unrealized gain on:
Pretax	[1]	124	1,611
Deferred Tax	[1]	(26)	(338)
Net	[1]	98	1,273
Fixed maturities — all other
Unrealized gain on:
Pretax		(30)	370
Deferred Tax		7	(78)
Net		(23)	292
Deferred policy acquisition costs — annuity segment
Unrealized gain on:
Pretax		(57)	(681)
Deferred Tax		12	143
Net		(45)	(538)
Annuity benefits accumulated
Unrealized gain on:
Pretax		(18)	(219)
Deferred Tax		3	46
Net		(15)	(173)
Life, accident and health reserves
Unrealized gain on:
Pretax			(1)
Deferred Tax			0
Net			(1)
Unearned revenue
Unrealized gain on:
Pretax		1	11
Deferred Tax		0	(2)
Net		$ 1	$ 9
[1]	Net unrealized gains on fixed maturity investments supporting AFG’s annuity benefits accumulated.

Investments - Schedule of sourc

Investments - Schedule of sources of net investment income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020		Mar. 31, 2019
Net Investment Income [Line Items]
Investment income		$ 549		$ 548
Investment expenses		(5)		(6)
Net investment income (b)		544	[1]	542
Fixed maturities
Net Investment Income [Line Items]
Investment income		491		469
Equity in earnings of partnerships and similar investments
Net Investment Income [Line Items]
Investment income		25		21
Other
Net Investment Income [Line Items]
Investment income		28		25
Accounting Standards Update 2016-01 | Equity securities
Net Investment Income [Line Items]
Investment income	[2]	(12)	[1]	11
Investment income | Equity securities
Net Investment Income [Line Items]
Investment income		$ 17		$ 22
[1]	Net investment income in the first three months of 2020 includes a loss of $6 million on investments held by the companies that comprise the Neon exited lines due primarily to the $7 million loss recorded on equity securities that are carried at fair value through net investment income.
[2]	Although the change in the fair value of the majority of AFG’s equity securities is recorded in realized gains (losses) on securities, AFG records holding gains and losses in net investment income on equity securities classified as “trading” under previous guidance and on a small portfolio of limited partnership and similar investments that do not qualify for the equity method of accounting.

Investments - Realized gains (l

Investments - Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		$ (505)	$ 186
Realized gains (losses) on securities		(551)	184
Net of tax
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		(399)	147
Realized — impairments		(36)	(2)
Realized gains (losses) on securities		(435)	145
Change in unrealized		(846)	381
Total pretax
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		(505)	186
Realized — impairments		(46)	(2)
Realized gains (losses) on securities		(551)	184
Change in unrealized		(1,071)	483
Fixed maturities
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		29	3
Realized — impairments		(61)	(3)
Realized gains (losses) on securities		(32)	0
Change in unrealized		(1,887)	853
Equity securities
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		(535)	182
Realized — impairments		0	0
Realized gains (losses) on securities		(535)	182
Change in unrealized		0	0
Mortgage loans and other investments
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		4	0
Realized — impairments		0	0
Realized gains (losses) on securities		4	0
Change in unrealized		0	0
Other, Including DPAC and reserves related to the annuity business
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	[1]	(3)	1
Realized — impairments	[1]	15	1
Realized gains (losses) on securities	[1]	12	2
Change in unrealized	[1]	816	(370)
Tax effects
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments		106	(39)
Realized — impairments		10	0
Realized gains (losses) on securities		116	(39)
Change in unrealized		$ 225	$ (102)
[1]	Primarily adjustments to deferred policy acquisition costs and reserves related to the annuity business.

Investments - Holding gains (lo

Investments - Holding gains (losses) on equity securities still held (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Holding Gains (Losses) on Equity Securities Still Held [Line Items]
Realized gains (losses) on securities still owned	$ (551)	$ 184
Included in net investment income	549	548
Equity securities
Holding Gains (Losses) on Equity Securities Still Held [Line Items]
Realized gains (losses) on securities still owned	(535)	182
Equity securities still owned | Equity securities | Accounting Standards Update 2016-01
Holding Gains (Losses) on Equity Securities Still Held [Line Items]
Net holding gains (losses) on equity securities	(545)	174
Equity securities still owned | Realized gains (losses) on securities | Equity securities | Accounting Standards Update 2016-01
Holding Gains (Losses) on Equity Securities Still Held [Line Items]
Realized gains (losses) on securities still owned	(540)	163
Equity securities still owned | Investment income | Equity securities | Accounting Standards Update 2016-01
Holding Gains (Losses) on Equity Securities Still Held [Line Items]
Included in net investment income	$ (5)	$ 11

Investments - Gross realized ga

Investments - Gross realized gains and losses on available for sale fixed maturity investment transactions (Details) - Fixed maturities - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Gross realized gains and losses on the sale of available for sale fixed maturity and equity security investments
Gross gains	$ 29	$ 6
Gross losses	$ (4)	$ (9)

Derivatives - Narrative (Detail

Derivatives - Narrative (Details)	3 Months Ended
	Mar. 31, 2020USD ($)swap	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Carrying value of collateral received to support purchased call options	$ 76,000,000		$ 577,000,000
Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Number of interest rate swaps designated and qualifying as a cash flow hedges | swap	12
Derivative, notional amount	$ 1,860,000,000		1,980,000,000
Gain (loss) reclassified from AOCI into net investment income	12,000,000	$ (2,000,000)
Collateral payable related to interest rate swaps	19,000,000
Collateral receivable related to interest rate swaps			20,000,000
Other assets | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value	125,000,000		50,000,000
Other liabilities | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value			$ (5,000,000)
Contract termination | Cash Flow Hedges | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	$ 83,000,000
Number of interest rate derivatives terminated | swap	1
Maximum | Other liabilities | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value	$ (1,000,000)

Derivatives - Derivatives that

Derivatives - Derivatives that do not qualify for hedge accounting under GAAP included in the Balance Sheet at fair value (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	$ 312	$ 1,026
Derivative liability, at fair value	3,109	3,735
MBS with embedded derivatives | Fixed maturities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	103	102
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits accumulated
Derivatives included in AFG' s Balance Sheet at fair value
Derivative liability, at fair value	3,099	3,730
Equity index call options | Equity index call options
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	209	924
Equity index put options | Other liabilities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative liability, at fair value	8	1
Reinsurance contracts (embedded derivative) | Other liabilities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative liability, at fair value	$ 2	$ 4

Derivatives - Gain (loss) inclu

Derivatives - Gain (loss) included in the Statement of Earnings for changes in the fair value of derivatives that do not qualify for hedge accounting (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ 19	$ (90)
MBS with embedded derivatives | Realized gains (losses) on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	4	6
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	647	(462)
Equity index call options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	(628)	366
Equity index put options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	(6)	1
Reinsurance contracts (embedded derivative) | Net investment income
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ 2	$ (1)

Deferred Policy Acquisition C_3

Deferred Policy Acquisition Costs - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Deferred Policy Acquisition Costs Disclosures [Abstract]
Accumulated amortization of present value of future profits	$ 156	$ 154

Deferred Policy Acquisition C_4

Deferred Policy Acquisition Costs - Progression of deferred policy acquisition costs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward]
Deferred policy acquisition costs and present value of future profits, beginning balance		$ 1,037	$ 1,682
Deferred policy acquisition costs and present value of future profits, additions		208	252
Deferred policy acquisition costs and present value of future profits, periodic amortization		(273)	(195)
Deferred policy acquisition costs and present value of future profits, change included in realized gains		10	2
Deferred policy acquisition costs and present value of future profits, foreign currency translation		0	1
Deferred policy acquisition costs and present value of future profits, change in unrealized		591	(295)
Deferred policy acquisition costs and present value of future profits, ending balance		1,573	1,447
P&C
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs, beginning balance		322	299
Deferred policy acquisition costs, additions		158	187
Deferred policy acquisition costs, periodic amortization		(170)	(175)
Deferred policy acquisition costs, foreign currency translation		0	1
Deferred policy acquisition costs, ending balance		310	312
Annuity and Other
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs, beginning balance		1,303	1,285
Deferred policy acquisition costs, additions		49	64
Deferred policy acquisition costs, periodic amortization		(98)	(15)
Deferred policy acquisition costs, change included in realized gains		10	2
Deferred policy acquisition costs, ending balance		1,264	1,336
Movement in Deferred Sales Inducements [Roll Forward]
Deferred sales inducements, beginning balance		75	86
Deferred sales inducements, additions		1	1
Deferred sales inducements, periodic amortization		(3)	(3)
Deferred sales inducements, change included in realized gains		0	0
Deferred sales inducements, ending balance		73	84
Movement in Present Value of Future Insurance Profits [Roll Forward]
Present value of future profits, beginning balance		36	42
Present value of future profits, periodic amortization		(2)	(2)
Present value of future profits, ending balance		34	40
Movement in Unrealized Gains (Losses) Related to Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward]
Unrealized investment gains (losses), beginning balance	[1]	(699)	(30)
Unrealized investment gains (losses), change in unrealized	[1]	591	(295)
Unrealized investment gains (losses), ending balance	[1]	(108)	(325)
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward]
Deferred policy acquisition costs and present value of future profits, beginning balance		715	1,383
Deferred policy acquisition costs and present value of future profits, additions		50	65
Deferred policy acquisition costs and present value of future profits, periodic amortization		(103)	(20)
Deferred policy acquisition costs and present value of future profits, change included in realized gains		10	2
Deferred policy acquisition costs and present value of future profits, change in unrealized		591	(295)
Deferred policy acquisition costs and present value of future profits, ending balance		1,263	1,135
Excluding Unrealized Gains | Annuity and Other
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward]
Deferred policy acquisition costs and present value of future profits, beginning balance		1,414	1,413
Deferred policy acquisition costs and present value of future profits, change in unrealized		0	0
Deferred policy acquisition costs and present value of future profits, ending balance		$ 1,371	$ 1,460
[1]	Adjustments to DPAC related to net unrealized gains/losses on securities and cash flow hedges.

Managed Investment Entities - N

Managed Investment Entities - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)collateralizedloanobligation	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Variable Interest Entity [Line Items]
Percentage of investment of most subordinate debt tranche, Minimum	15.00%
Percentage of investment of most subordinate debt tranche, Maximum	100.00%
Number of collateralized loan obligation entities | collateralizedloanobligation	11
Face amount of managed investment entities liabilities purchased by subsidiaries after issuance date	$ 57
Amount paid by subsidiaries to purchase managed investment entities liabilities after issuance date	39
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	818		$ 146
Difference between aggregate unpaid principal balance and carrying value of CLOs' debt	747		129
Carrying amount of CLO loans in default	20		10
Aggregate unpaid principal balance of variable interest entity loans in default	50		25
Available for sale (AFS) fixed maturities	46,134		46,505
Maximum
Variable Interest Entity [Line Items]
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities	1	$ 1
Collateralized loan obligations | Managed by third parties
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	4,138		4,280
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	161	$ 193	$ 165
Variable interest entity, primary beneficiary | Subordinated Debt Obligations
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	$ 81

Managed Investment Entities - S

Managed Investment Entities - Selected financial information related to CLOs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Gains (losses) on change in fair value of assets/liabilities:
Assets	[1]	$ (679)	$ 87
Liabilities	[1]	636	(87)
Management fees paid to AFG		4	3
CLO earnings (losses) attributable to AFG shareholders	[2]	(36)	11
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Investment in CLO tranches at end of period		$ 161	$ 193	$ 165
[1]	Included in revenues in AFG’s Statement of Earnings.
[2]	Included in earnings before income taxes in AFG’s Statement of Earnings.

Goodwill and Other Intangibles

Goodwill and Other Intangibles - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the goodwill balance during the period	$ 0
Goodwill	207,000,000		$ 207,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	40,000,000		43,000,000
Accumulated amortization	53,000,000		$ 50,000,000
Amortization of intangible assets	$ 3,000,000	$ 3,000,000

Long-Term Debt - Narrative (Det

Long-Term Debt - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Long-term Debt, Fiscal Year Maturity [Abstract]
Scheduled principal payments on debt remainder of fiscal 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
Scheduled principal payments on debt in year six	0
AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Revolving credit line	500,000,000
Amount borrowed under 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%

Long-Term Debt - Schedule of lo

Long-Term Debt - Schedule of long-term debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Summary of Carrying value of long-term debt
Principal	$ 1,493	$ 1,493
Discount and Issue Costs	(20)	(20)
Carrying Value	1,473	1,473
Senior Notes | AFG
Summary of Carrying value of long-term debt
Principal	1,018	1,018
Discount and Issue Costs	(5)	(5)
Carrying Value	$ 1,013	1,013
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	$ 590	590
Discount and Issue Costs	(2)	(2)
Carrying Value	$ 588	588
Senior Notes | 3.50% Senior Notes due August 2026 | AFG
Debt Instrument [Line Items]
Interest rate on debt instruments	3.50%
Summary of Carrying value of long-term debt
Principal	$ 425	425
Discount and Issue Costs	(3)	(3)
Carrying Value	422	422
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	475	475
Discount and Issue Costs	(15)	(15)
Carrying Value	$ 460	460
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	(6)	(6)
Carrying Value	$ 194	194
Subordinated Debentures | 6% Subordinated Debentures due November 2055 | AFG
Debt Instrument [Line Items]
Interest rate on debt instruments	6.00%
Summary of Carrying value of long-term debt
Principal	$ 150	150
Discount and Issue Costs	(5)	(5)
Carrying Value	$ 145	145
Subordinated Debentures | 5.875% Subordinated Debentures due in 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

Shareholders' Equity - Preferre

Shareholders' Equity - Preferred stock authorized for issuance (Details)	Mar. 31, 2020$ / sharesshares
Voting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, shares authorized | shares	12,500,000
Preferred Stock, par value (in USD per share) | $ / shares	$ 0
Nonvoting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, shares authorized | shares	12,500,000
Preferred Stock, par value (in USD per share) | $ / shares	$ 0

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to stock incentive plans	$ 5	$ 6
Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Common Stock, shares issued (shares)	227,867
Restricted Common Stock, fair value per share (USD per share)	$ 104.15

Shareholders' Equity - Progress

Shareholders' Equity - Progression of the components of accumulated other comprehensive income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		$ 863
Other comprehensive income (loss), net of tax		(829)	$ 396
AOCI ending balance		32
Accumulated Net Investment Gain (Loss) Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, Pretax		(1,095)	487
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, tax		230	(103)
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, net of tax		(865)	384
Reclassification from accumulated other comprehensive income, pretax	[1]	24	(4)
Reclassification from accumulated other comprehensive income, tax	[1]	(5)	1
Reclassification from accumulated other comprehensive income, net of tax		19	(3)
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		(1,071)	483
Other comprehensive income (loss), tax		225	(102)
Other comprehensive income (loss), net of tax		(846)	381
Accumulated Net Investment Gain (Loss) Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, net of tax		0	0
Reclassification from accumulated other comprehensive income, net of tax	[1]	0	0
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), net of tax		0	0
Accumulated Net Investment Gain (Loss) Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, net of tax		(865)	384
Reclassification from accumulated other comprehensive income, net of tax		19	(3)
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		862	83
Other comprehensive income (loss), net of tax		(846)	381
AOCI ending balance		16	464
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		34	14
Other comprehensive income (loss), tax		(7)	(3)
Other comprehensive income (loss), net of tax		27	11
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), net of tax		0	0
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		17	(11)
Other comprehensive income (loss), net of tax		27	11
AOCI ending balance		44	0
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		(10)	4
Other comprehensive income (loss), tax		0	0
Other comprehensive income (loss), net of tax		(10)	4
Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), net of tax		(2)	0
Accumulated Foreign Currency Adjustment Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		(9)	(16)
Other comprehensive income (loss), net of tax		(12)	4
AOCI ending balance		(21)	(12)
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		0	0
Other comprehensive income (loss), tax		0	0
Other comprehensive income (loss), net of tax		0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), net of tax		0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		(7)	(8)
Other comprehensive income (loss), net of tax		0	0
AOCI ending balance		(7)	(8)
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		(1,047)	501
Other comprehensive income (loss), tax		218	(105)
Other comprehensive income (loss), net of tax		(829)	396
AOCI Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), net of tax		(2)	0
AOCI Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		863	48
Other comprehensive income (loss), net of tax		(831)	396
AOCI ending balance		$ 32	$ 444
[1]	The reclassification adjustment out of net unrealized gains (losses) on securities affected the following lines in AFG’s Statement of Earnings: OCI component Affected line in the statement of earnings Pretax Realized gains (losses) on securities Tax Provision (credit) for income taxes

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Statutory rate of income taxes	21.00%	21.00%
Operating loss carryforwards subject to SRLY tax rules will expire unutilized at December 31, 2020	$ 23

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of income taxes at the statutory rate to the provision for income taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Earnings (loss) before income taxes (“EBT”)	$ (388)	$ 413
Income taxes at statutory rate	(81)	87
Effect of stock-based compensation	(4)	(2)
Effect of tax exempt interest	(3)	(4)
Effect of dividends received deduction	(1)	(1)
Effect of nondeductible expenses	2	2
Effect of change in valuation allowance	2	2
Effect of foreign operations	1	0
Effect of other income tax reconciliation	0	3
Provision for income taxes as shown on the Statement of Earnings	$ (84)	$ 87
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income taxes at statutory rate as a percentage of EBT	21.00%	21.00%
Effect of stock-based compensation as a percentage of EBT	1.00%	0.00%
Effect of tax exempt interest as a percentage of EBT	1.00%	(1.00%)
Effect of dividends received deduction as a percentage of EBT	0.00%	0.00%
Effect of nondeductible expenses as a percentage of EBT	(1.00%)	0.00%
Effect of change in valuation allowance as a percentage of EBT	(1.00%)	0.00%
Effect of foreign operations as a percentage of EBT	0.00%	0.00%
Effect of other income tax reconciliation as a percentage of EBT	1.00%	1.00%
Provision for income taxes as shown on the Statement of Earnings as a percentage of EBT	22.00%	21.00%

Contingencies - Narrative (Deta

Contingencies - Narrative (Details) - Run-off Long-term Care and Life $ in Millions	Dec. 24, 2015USD ($)
Loss Contingencies [Line Items]
Contingent capital support agreement amount	$ 35
Contingent capital support agreement contractual term	5 years

Insurance - Narrative (Details)

Insurance - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Insurance [Line Items]
Loss and LAE incurred in Neon exited lines	$ 707	[1]	$ 692
Neon Capital Limited
Insurance [Line Items]
Loss and LAE incurred in Neon exited lines	$ 40
[1]	Includes $40 million in losses and LAE incurred in the Neon exited lines in the first three months of 2020 .

Insurance - Analysis of changes

Insurance - Analysis of changes in the liability for losses and loss adjustment expenses, net of reinsurance (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Analysis of changes in the liability for losses and loss adjustment expenses, net of reinsurance
Balance at beginning of year	$ 10,232		$ 9,741
Less reinsurance recoverables, net of allowance	3,024		2,942
Net liability at beginning of year	7,208		6,799
Liability for losses and loss adjustment expenses, period increase (decrease) [Abstract]
Provision for losses and LAE occurring in the current period	749		737
Net increase (decrease) in the provision for claims of prior years	(42)		(45)
Total losses and LAE incurred ()	707	[1]	692
Payments for losses and LAE of:
Current year	(75)		(89)
Prior years	(676)		(615)
Total payments	(751)		(704)
Foreign currency translation and other	(22)		1
Net liability at end of period	7,142		6,788
Add back reinsurance recoverables, net of allowance	2,964		2,835
Gross unpaid losses and LAE included in the balance sheet at end of period	$ 10,106		$ 9,623
[1]	Includes $40 million in losses and LAE incurred in the Neon exited lines in the first three months of 2020 .

Insurance - Recoverables from r

Insurance - Recoverables from reinsurance, progression of allowance for expected credit losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 18
Impact of adoption of new accounting principles	(13)	$ (6)
Provision (credit) for expected credit losses	1
Write-offs charged against the allowance	0
Ending Balance	$ 13

Insurance - Premiums receivable

Insurance - Premiums receivable, progression of allowance for expected credit losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 13
Impact of adoption of new accounting principles	(9)	$ (3)
Provision (credit) for expected credit losses	(1)
Write-offs charged against the allowance	0
Ending Balance	$ 9

Subsequent Events - Narrative (

Subsequent Events - Narrative (Details) - AFG - Senior Notes - Senior Notes due in April 2030 - Subsequent event $ in Millions	Apr. 02, 2020USD ($)
Subsequent Event [Line Items]
Senior Notes, aggregate principal amount	$ 300
Interest rate on debt instruments	5.25%