American Financial (AFG) 10-Q 5 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	May 01, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	AMERICAN FINANCIAL GROUP INC
Entity Central Index Key	1,042,046
Document Type	10-Q
Document Period End Date	Mar. 31, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		87,636,894

Consolidated Balance Sheet (Una

Consolidated Balance Sheet (Unaudited) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Assets:
Cash and cash equivalents	$ 1,890	$ 2,107
Investments:
Fixed maturities, available for sale at fair value (amortized cost — $35,445 and $33,735)	36,456	34,544
Fixed maturities, trading at fair value	359	359
Equity securities, available for sale at fair value (cost — $1,356 and $1,351)	1,579	1,502
Equity securities, trading at fair value	58	56
Mortgage loans	1,159	1,147
Policy loans	190	192
Equity index call options	573	492
Real estate and other investments	1,086	1,034
Total cash and investments	43,350	41,433
Recoverables from reinsurers	2,735	2,737
Prepaid reinsurance premiums	533	539
Agents’ balances and premiums receivable	989	997
Deferred policy acquisition costs	1,205	1,239
Assets of managed investment entities	5,331	4,765
Other receivables	875	908
Variable annuity assets (separate accounts)	614	600
Other assets	1,633	1,655
Goodwill	199	199
Total assets	57,464	55,072
Liabilities and Equity:
Unpaid losses and loss adjustment expenses	8,621	8,563
Unearned premiums	2,174	2,171
Annuity benefits accumulated	31,002	29,907
Life, accident and health reserves	687	691
Payable to reinsurers	621	634
Liabilities of managed investment entities	5,101	4,549
Long-term debt	1,283	1,283
Variable annuity liabilities (separate accounts)	614	600
Other liabilities	2,166	1,755
Total liabilities	52,269	50,153
Shareholders’ equity:
Common Stock, no par value — 200,000,000 shares authorized — 87,591,671 and 86,924,399 shares outstanding	88	87
Capital surplus	1,138	1,111
Retained earnings	3,466	3,343
Accumulated other comprehensive income, net of tax	499	375
Total shareholders’ equity	5,191	4,916
Noncontrolling interests	4	3
Total equity	5,195	4,919
Total liabilities and equity	$ 57,464	$ 55,072

Consolidated Balance Sheet (Un3

Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Fixed maturities, available for sale at amortized cost	$ 35,445	$ 33,735
Equity securities, available for sale at cost	$ 1,356	$ 1,351
Common Stock, par value (USD per share)	$ 0	$ 0
Common Stock, shares authorized	200,000,000	200,000,000
Common Stock, shares outstanding	87,591,671	86,924,399

Consolidated Statement of Earni

Consolidated Statement of Earnings (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenues:
Property and casualty insurance net earned premiums	$ 1,022	$ 998
Life, accident and health net earned premiums	6	6
Net investment income	435	411
Realized gains (losses) on securities	3	(18)
Income (loss) of managed investment entities:
Investment income	51	45
Gain (loss) on change in fair value of assets/liabilities	0	(13)
Other income	59	46
Total revenues	1,576	1,475
Costs and Expenses:
Property and casualty insurance: Losses and loss adjustment expenses	609	581
Property and casualty insurance: Commissions and other underwriting expenses	339	334
Annuity benefits	196	228
Life, accident and health benefits	9	9
Annuity and supplemental insurance acquisition expenses	53	35
Interest charges on borrowed money	21	18
Expenses of managed investment entities	41	35
Other expenses	85	79
Total costs and expenses	1,353	1,319
Earnings before income taxes	223	156
Provision for income taxes	68	52
Net earnings, including noncontrolling interests	155	104
Less: Net earnings attributable to noncontrolling interests	2	3
Net Earnings Attributable to Shareholders	$ 153	$ 101
Earnings Attributable to Shareholders per Common Share:
Basic (USD per share)	$ 1.76	$ 1.16
Diluted (USD per share)	$ 1.72	$ 1.14
Average number of Common Shares:
Basic (shares)	87.2	86.9
Diluted (shares)	89.3	88.5
Cash dividends per Common Share (USD per share)	$ 0.3125	$ 0.28
Supplemental disclosure of Realized gains on securities:
Realized gains before impairments	$ 9	$ 34
Losses on securities with impairment	(6)	(51)
Non-credit portion recognized in other comprehensive income (loss)	0	(1)
Impairment charges recognized in earnings	(6)	(52)
Total realized gains (losses) on securities	$ 3	$ (18)

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net earnings, including noncontrolling interests	$ 155	$ 104
Net unrealized gains on securities:
Unrealized holding gains on securities arising during the period	125	125
Reclassification adjustment for realized (gains) losses included in net earnings	0	11
Total net unrealized gains on securities	125	136
Net unrealized gains (losses) on cash flow hedges	(1)	3
Foreign currency translation adjustments	0	6
Pension and other postretirement plans adjustments	0	1
Other comprehensive income, net of tax	124	146
Total comprehensive income, net of tax	279	250
Less: Comprehensive income attributable to noncontrolling interests	2	5
Comprehensive income attributable to shareholders	$ 277	$ 245

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 Comprehensive Income	Noncontrolling interests
Beginning Balance, shares at Dec. 31, 2015			87,474,452
Beginning Balance at Dec. 31, 2015	$ 4,770	$ 4,592		$ 1,301	$ 2,987	$ 304	$ 178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	104	101			101		3
Other comprehensive income (loss)	146	144				144	2
Dividends on Common Stock	(24)	(24)			(24)
Shares issued:
Exercise of stock options, shares			279,165
Exercise of stock options	10	10		10
Restricted stock awards, shares			317,230
Restricted stock awards	0	0		0
Other benefit plans, shares			47,566
Other benefit plans	3	3		3
Dividend reinvestment plan, shares			3,736
Stock-based compensation expense	7	7		7
Shares acquired and retired, shares			(1,128,128)
Shares acquired and retired	(76)	(76)		(16)	(60)
Shares exchanged — benefit plans, shares			(27,551)
Shares exchanged — benefit plans	(2)	(2)		0	(2)
Forfeitures of restricted stock, shares			(180)
Forfeitures of restricted stock	0	0		0
Other	(1)						(1)
Ending Balance, shares at Mar. 31, 2016			86,966,290
Ending Balance at Mar. 31, 2016	$ 4,937	4,755		1,305	3,002	448	182
Beginning Balance, shares at Dec. 31, 2016	86,924,399		86,924,399
Beginning Balance at Dec. 31, 2016	$ 4,919	4,916		1,198	3,343	375	3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	155	153			153		2
Other comprehensive income (loss)	124	124				124	0
Dividends on Common Stock	(27)	(27)			(27)
Shares issued:
Exercise of stock options, shares			411,167
Exercise of stock options	15	15		15
Restricted stock awards, shares			232,250
Restricted stock awards	0	0		0
Other benefit plans, shares			54,453
Other benefit plans	5	5		5
Dividend reinvestment plan, shares			3,277
Dividend reinvestment plan	0	0		0
Stock-based compensation expense	8	8		8
Shares exchanged — benefit plans, shares			(32,176)
Shares exchanged — benefit plans	(3)	(3)		0	(3)
Forfeitures of restricted stock, shares			(1,699)
Forfeitures of restricted stock	0	0		0
Other	$ (1)						(1)
Ending Balance, shares at Mar. 31, 2017	87,591,671		87,591,671
Ending Balance at Mar. 31, 2017	$ 5,195	$ 5,191		$ 1,226	$ 3,466	$ 499	$ 4

Consolidated Statement of Cash

Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating Activities:
Net earnings, including noncontrolling interests	$ 155	$ 104
Adjustments:
Depreciation and amortization	38	28
Annuity benefits	196	228
Realized (gains) losses on investing activities	(17)	15
Net sales of trading securities	3	71
Deferred annuity and life policy acquisition costs	(67)	(68)
Change in:
Reinsurance and other receivables	63	197
Other assets	(58)	2
Insurance claims and reserves	57	(26)
Payable to reinsurers	(13)	(90)
Other liabilities	45	15
Managed investment entities’ assets/liabilities	(487)	(55)
Other operating activities, net	9	(13)
Net cash provided by (used in) operating activities	(76)	408
Investing Activities:
Purchases of fixed maturities	(2,879)	(2,125)
Purchases of equity securities	(22)	(74)
Purchases of mortgage loans	(23)	(131)
Purchases of equity index call options and other investments	(181)	(139)
Purchases of real estate, property and equipment	(11)	(18)
Proceeds from maturities and redemptions of fixed maturities	1,511	840
Proceeds from repayments of mortgage loans	12	101
Proceeds from sales of fixed maturities	38	225
Proceeds from sales of equity securities	14	55
Proceeds from sales and settlements of equity index call options and other investments	174	4
Proceeds from sales of real estate, property and equipment	24	5
Managed investment entities:
Purchases of investments	(910)	(239)
Proceeds from sales and redemptions of investments	1,058	290
Other investing activities, net	1	(63)
Net cash used in investing activities	(1,194)	(1,269)
Financing Activities:
Annuity receipts	1,290	1,435
Annuity surrenders, benefits and withdrawals	(567)	(503)
Net transfers from variable annuity assets	17	9
Issuances of managed investment entities’ liabilities	537	31
Retirements of managed investment entities’ liabilities	(212)	(11)
Issuances of Common Stock	15	13
Repurchases of Common Stock	0	(76)
Cash dividends paid on Common Stock	(27)	(24)
Other financing activities, net	0	(2)
Net cash provided by financing activities	1,053	872
Net Change in Cash and Cash Equivalents	(217)	11
Cash and cash equivalents at beginning of period	2,107	1,220
Cash and cash equivalents at end of period	$ 1,890	$ 1,231

Accounting Policies

Accounting Policies	3 Months Ended
	Mar. 31, 2017
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, 2017 , 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 significant nonrecurring fair value measurements in the first three months of 2017 . Investments Fixed maturity and equity securities classified as “available for sale” are reported at fair value with unrealized gains and losses included in accumulated other comprehensive income (“AOCI”) in AFG’s Balance Sheet. Fixed maturity and equity 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. In January 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-01, which, among other things, will require all equity securities currently classified as “available for sale” to be reported at fair value, with holding gains and losses recognized in net income, instead of AOCI. AFG will be required to adopt this guidance effective January 1, 2018. Premiums and discounts on fixed maturity securities are amortized using the 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. Gains or losses on securities are determined on the specific identification basis. When a decline in the value of a specific investment is considered to be other-than-temporary at the balance sheet date, a provision for impairment is charged to earnings (included in realized gains (losses) on securities) and the cost basis of that investment is reduced. If management can assert that it does not intend to sell an impaired fixed maturity security and it is not more likely than not that it will have to sell the security before recovery of its amortized cost basis, then the other-than-temporary impairment 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 of an other-than-temporary impairment 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 impairment 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 charge to earnings is recorded to reduce the amortized cost of that security to fair value. 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 MBS) and (ii) the equity-based component of certain annuity products (included in annuity benefits accumulated) and related equity index call 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. Any hedge ineffectiveness is immediately recorded in current period 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. For derivatives that are designated and qualify as highly effective fair value hedges, changes in the fair value of the derivative, along with changes in the fair value of the hedged item attributable to the hedged risk, are recognized in current period earnings. AFG has entered into an interest rate swap that qualifies as a highly effective fair value hedge to mitigate the interest rate risk associated with fixed-rate long-term debt by economically converting certain fixed-rate debt obligations to floating-rate obligations. Since the terms of the swap match the terms of the hedged debt, changes in the fair value of the swap are offset by changes in the fair value of the hedged debt attributable to changes in interest rates. Accordingly, the net impact on AFG’s current period earnings is that the interest expense associated with the hedged debt is effectively recorded at the floating rate. 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, long-term care 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 the 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 expense and decreases for policy charges are credited to other income. 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 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. 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. Noncontrolling Interests For balance sheet purposes, noncontrolling interests represents 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. 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. 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. See Note K — “ Shareholders’ Equity ” for further information. In the fourth quarter of 2016, AFG adopted ASU 2016-09, which, among other things, requires excess tax benefits or deficiencies for share-based payments to be recorded through income tax expense in the statement of earnings instead of directly to capital surplus (as required under the previous guidance). In addition, under the new guidance, AFG elected to account for forfeitures of awards when they occur rather than accruing expense based on an estimate of expected forfeitures (as required under the previous guidance). The resulting cumulative effect of accounting change of less than $1 million was recorded directly to retained earnings on January 1, 2016. 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 2017 and 2016 — 2.1 million and 1.6 million , respectively. AFG’s weighted average diluted shares outstanding for the first three months of 2016 excludes 0.8 million anti-dilutive potential common shares related to stock compensation plans. There were no anti-dilutive potential common shares for the first three months of 2017 . 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 and property and equipment. “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. Effective October 1, 2016, AFG early adopted (on a retrospective basis) ASU 2016-15, which addresses the diversity in practice in how certain cash receipts and cash payments are presented in the statement of cash flows. Among other things, this guidance requires proceeds received from the settlement of corporate-owned life insurance policies to be classified as cash inflows from investing activities and allows premiums paid for policies to be reported as cash outflows either from investing activities or operating activities. AFG has elected to show all corporate-owned life insurance activity in investing activities. Prior to adoption of this guidance, AFG accounted for these transactions as operating activities. In addition, ASU 2016-15 clarifies when distributions received from investees accounted under the equity method should be accounted for as a cash inflow from operating activities or as a cash inflow from investing activities. AFG had previously accounted for all distributions from investments accounted for under the equity method as investing activities. The new guidance solely related to the presentation of certain transactions in the statement of cash flows. Accordingly, adoption of this guidance did not impact AFG’s results of operations or financial position. Revenue Recognition Guidance Effective in 2018 In May 2014, the FASB issued ASU 2014-09, which requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Revenue is recognized when (or as) the entity satisfies a performance obligation under the contract. The new guidance also updates the accounting for certain costs associated with obtaining and fulfilling contracts with customers and requires disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Revenue recognition for insurance contracts and financial instruments, which are AFG’s primary sources of revenue, is excluded from the scope of the new guidance. AFG will adopt the new guidance effective January 1, 2018. Because the new guidance does not apply to the vast majority of AFG’s business, management does not expect the adoption of this guidance to have a material impact on AFG’s results of operations or financial position. Based on implementation efforts to date, management believes that the new standard would only have applied to 2% of AFG’s 2016 consolidated revenues.

Acquisition of Business

Acquisition of Business	3 Months Ended
	Mar. 31, 2017
Disclosure Text Block [Abstract]
Acquisition of Business	Acquisition of Business Acquisition of Noncontrolling Interest in National Interstate Corporation In November 2016, AFG acquired the 49% of National Interstate Corporation (“NATL”) not previously owned by AFG’s wholly-owned subsidiary, Great American Insurance Company, for $315 million ( $32.00 per share) in a merger transaction. In addition, NATL paid a one-time special cash dividend of $0.50 per share to its shareholders immediately prior to the merger closing. Because NATL was already a consolidated subsidiary of AFG prior to the merger, the acquisition was accounted for as an equity transaction.

Segments of Operations

Segments of Operations	3 Months Ended
	Mar. 31, 2017
Segment Reporting [Abstract]
Segments of Operations	Segments of Operations AFG manages its business as four segments: (i) Property and casualty insurance, (ii) Annuity, (iii) Run-off long-term care and life and (iv) Other, which includes holding company costs. 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, trucks and recreational vehicles, inland and ocean marine, agricultural-related products and other property coverages, (ii) Specialty casualty, which includes primarily excess and surplus, general liability, executive liability, professional liability, umbrella and excess liability, specialty coverage 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 leasing and financing institutions (including collateral and lender-placed mortgage property insurance), surety and fidelity 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 markets traditional fixed and fixed-indexed annuities in the retail, financial institutions and education markets. AFG’s reportable segments and their components were determined based primarily upon similar economic characteristics, products and services. The following tables (in millions) show AFG’s revenues and earnings before income taxes by segment and sub-segment. Three months ended March 31, 2017 2016 Revenues Property and casualty insurance: Premiums earned: Specialty Property and transportation $ 342 $ 339 Specialty casualty 508 502 Specialty financial 147 132 Other specialty 25 25 Total premiums earned 1,022 998 Net investment income 86 83 Other income (a) 16 3 Total property and casualty insurance 1,124 1,084 Annuity: Net investment income 347 315 Other income 27 26 Total annuity 374 341 Run-off long-term care and life 12 12 Other 63 56 Total revenues before realized gains (losses) 1,573 1,493 Realized gains (losses) on securities 3 (18 ) Total revenues $ 1,576 $ 1,475 Earnings Before Income Taxes Property and casualty insurance: Underwriting: Specialty Property and transportation $ 43 $ 32 Specialty casualty 15 29 Specialty financial 22 23 Other specialty (1 ) 2 Other lines (1 ) 1 Total underwriting 78 87 Investment and other income, net (a) 93 75 Total property and casualty insurance 171 162 Annuity 96 53 Run-off long-term care and life — (1 ) Other (b) (47 ) (40 ) Total earnings before realized gains (losses) and income taxes 220 174 Realized gains (losses) on securities 3 (18 ) Total earnings before income taxes $ 223 $ 156 (a) Includes pretax income of $13 million (before noncontrolling interest) from the sale of a hotel in the first quarter of 2017. (b) Includes holding company interest and expenses.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2017
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 and 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, mortgage-backed securities (“MBS”) 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 in the circumstances. AFG’s Level 3 is comprised of 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. As discussed in Note A — “ Accounting Policies — Managed Investment Entities ,” 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. 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 25 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, 2017 Assets: Available for sale (“AFS”) fixed maturities: U.S. Government and government agencies $ 122 $ 158 $ 8 $ 288 States, municipalities and political subdivisions — 6,758 143 6,901 Foreign government — 138 — 138 Residential MBS — 3,541 175 3,716 Commercial MBS — 1,224 29 1,253 Asset-backed securities (“ABS”) — 5,998 594 6,592 Corporate and other 30 16,710 828 17,568 Total AFS fixed maturities 152 34,527 1,777 36,456 Trading fixed maturities 26 333 — 359 Equity securities — AFS and trading 1,383 81 173 1,637 Assets of managed investment entities (“MIE”) 896 4,409 26 5,331 Variable annuity assets (separate accounts) (*) — 614 — 614 Equity index call options — 573 — 573 Other assets — derivatives — — — — Total assets accounted for at fair value $ 2,457 $ 40,537 $ 1,976 $ 44,970 Liabilities: Liabilities of managed investment entities $ 857 $ 4,219 $ 25 $ 5,101 Derivatives in annuity benefits accumulated — — 1,963 1,963 Derivatives in long-term debt — — — — Other liabilities — derivatives — 32 — 32 Total liabilities accounted for at fair value $ 857 $ 4,251 $ 1,988 $ 7,096 December 31, 2016 Assets: Available for sale fixed maturities: U.S. Government and government agencies $ 133 $ 174 $ 8 $ 315 States, municipalities and political subdivisions — 6,641 140 6,781 Foreign government — 136 — 136 Residential MBS — 3,445 190 3,635 Commercial MBS — 1,468 25 1,493 Asset-backed securities — 5,475 484 5,959 Corporate and other 29 15,484 712 16,225 Total AFS fixed maturities 162 32,823 1,559 34,544 Trading fixed maturities 30 329 — 359 Equity securities — AFS and trading 1,305 79 174 1,558 Assets of managed investment entities 380 4,356 29 4,765 Variable annuity assets (separate accounts) (*) — 600 — 600 Equity index call options — 492 — 492 Other assets — derivatives — 1 — 1 Total assets accounted for at fair value $ 1,877 $ 38,680 $ 1,762 $ 42,319 Liabilities: Liabilities of managed investment entities $ 363 $ 4,158 $ 28 $ 4,549 Derivatives in annuity benefits accumulated — — 1,759 1,759 Derivatives in long-term debt — (1 ) — (1 ) Other liabilities — derivatives — 30 — 30 Total liabilities accounted for at fair value $ 363 $ 4,187 $ 1,787 $ 6,337 (*) Variable annuity liabilities equal the fair value of variable annuity assets. Transfers between Level 1 and Level 2 for all periods presented were a result of increases or decreases in observable trade activity. During the first three months of 2017 , there were no transfers between Level 1 and Level 2. During the first three months of 2016 , there was one perpetual preferred stock with a fair value of $8 million transferred from Level 2 to Level 1 and three perpetual preferred stocks with an aggregate fair value of $6 million transferred from Level 1 to Level 2. Approximately 4% of the total assets carried at fair value on March 31, 2017 , were Level 3 assets. Approximately 75% ( $1.49 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. Since internally developed Level 3 asset fair values represent less than 10% of AFG’s Shareholders’ Equity, any justifiable changes in unobservable inputs used to determine internally developed fair values would not have a material impact on AFG’s financial position. The only significant Level 3 assets or liabilities carried at fair value in the financial statements that were not measured using broker quotes are the derivatives embedded in AFG’s fixed-indexed annuity liabilities, which are measured using a discounted cash flow approach and had a fair value of $1.96 billion at March 31, 2017 . The following table presents information about the unobservable inputs used by management in determining fair value of these embedded derivatives. See Note F — “ Derivatives .” Unobservable Input Range Adjustment for insurance subsidiary’s credit risk 0.2% – 2.8% over the risk free rate Risk margin for uncertainty in cash flows 0.68% reduction in the discount rate Surrenders 3% – 21% of indexed account value Partial surrenders 2% – 10% of indexed account value Annuitizations 0.1% – 1% of indexed account value Deaths 1.5% – 8.0% of indexed account value Budgeted option costs 2.4% – 3.6% of indexed account value The range of adjustments for insurance subsidiary’s credit risk 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 annuity products with an expected range of 6% to 10% in the majority of future calendar years ( 3% to 21% over all periods). Increasing the budgeted option cost or risk margin for uncertainty in cash flows assumptions in the table above would increase the fair value of the fixed-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 2017 and 2016 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, 2016 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2017 AFS fixed maturities: U.S. government agency $ 8 $ — $ — $ — $ — $ — $ — $ 8 State and municipal 140 — 3 — — — — 143 Residential MBS 190 1 — 1 (8 ) 7 (16 ) 175 Commercial MBS 25 — — — — 4 — 29 Asset-backed securities 484 — — 104 (11 ) 17 — 594 Corporate and other 712 1 4 120 (38 ) 29 — 828 Total AFS fixed maturities 1,559 2 7 225 (57 ) 57 (16 ) 1,777 Equity securities 174 (6 ) 7 12 — — (14 ) 173 Assets of MIE 29 (1 ) — 2 — — (4 ) 26 Total Level 3 assets $ 1,762 $ (5 ) $ 14 $ 239 $ (57 ) $ 57 $ (34 ) $ 1,976 Embedded derivatives $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total Level 3 liabilities (*) $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2015 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2016 AFS fixed maturities: U.S. government agency $ 15 $ — $ — $ — $ — $ — $ — $ 15 State and municipal 89 — 3 — — — — 92 Residential MBS 224 1 — — (7 ) 11 (16 ) 213 Commercial MBS 39 — — — (1 ) — — 38 Asset-backed securities 470 — (6 ) 4 (8 ) 41 — 501 Corporate and other 633 (2 ) 15 86 (7 ) 5 — 730 Total AFS fixed maturities 1,470 (1 ) 12 90 (23 ) 57 (16 ) 1,589 Equity securities 140 (17 ) 8 12 — 15 — 158 Assets of MIE 26 (2 ) — — — — — 24 Total Level 3 assets $ 1,636 $ (20 ) $ 20 $ 102 $ (23 ) $ 72 $ (16 ) $ 1,771 Embedded derivatives $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) Total Level 3 liabilities (*) $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) (*) As discussed previously, 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, 2017 Financial assets: Cash and cash equivalents $ 1,890 $ 1,890 $ 1,890 $ — $ — Mortgage loans 1,159 1,158 — — 1,158 Policy loans 190 190 — — 190 Total financial assets not accounted for at fair value $ 3,239 $ 3,238 $ 1,890 $ — $ 1,348 Financial liabilities: Annuity benefits accumulated (*) $ 30,799 $ 29,997 $ — $ — $ 29,997 Long-term debt 1,283 1,382 — 1,379 3 Total financial liabilities not accounted for at fair value $ 32,082 $ 31,379 $ — $ 1,379 $ 30,000 December 31, 2016 Financial assets: Cash and cash equivalents $ 2,107 $ 2,107 $ 2,107 $ — $ — Mortgage loans 1,147 1,146 — — 1,146 Policy loans 192 192 — — 192 Total financial assets not accounted for at fair value $ 3,446 $ 3,445 $ 2,107 $ — $ 1,338 Financial liabilities: Annuity benefits accumulated (*) $ 29,703 $ 28,932 $ — $ — $ 28,932 Long-term debt 1,284 1,356 — 1,353 3 Total financial liabilities not accounted for at fair value $ 30,987 $ 30,288 $ — $ 1,353 $ 28,935 (*) Excludes $203 million and $204 million of life contingent annuities in the payout phase at March 31, 2017 and December 31, 2016 , respectively. The carrying amount of cash and cash equivalents approximates fair value. Fair values for mortgage loans are estimated by discounting the future contractual cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings. The fair value of policy loans is estimated to approximate carrying value; policy loans have no defined maturity dates and are inseparable from insurance contracts. The fair value of annuity benefits was estimated based on expected cash flows discounted using forward interest rates adjusted for the Company’s credit risk and includes the impact of maintenance expenses and capital costs. Fair values of long-term debt are based primarily on quoted market prices.

Investments

Investments	3 Months Ended
	Mar. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Available for sale fixed maturities and equity securities at March 31, 2017 and December 31, 2016 , consisted of the following (in millions): March 31, 2017 December 31, 2016 Amortized Cost Gross Unrealized Net Unrealized Fair Value Amortized Cost Gross Unrealized Net Unrealized Fair Value Gains Losses Gains Losses Fixed maturities: U.S. Government and government agencies $ 289 $ 2 $ (3 ) $ (1 ) $ 288 $ 315 $ 3 $ (3 ) $ — $ 315 States, municipalities and political subdivisions 6,736 213 (48 ) 165 6,901 6,650 200 (69 ) 131 6,781 Foreign government 133 5 — 5 138 131 5 — 5 136 Residential MBS 3,432 295 (11 ) 284 3,716 3,367 281 (13 ) 268 3,635 Commercial MBS 1,211 43 (1 ) 42 1,253 1,446 49 (2 ) 47 1,493 Asset-backed securities 6,548 74 (30 ) 44 6,592 5,962 43 (46 ) (3 ) 5,959 Corporate and other 17,096 544 (72 ) 472 17,568 15,864 473 (112 ) 361 16,225 Total fixed maturities $ 35,445 $ 1,176 $ (165 ) $ 1,011 $ 36,456 $ 33,735 $ 1,054 $ (245 ) $ 809 $ 34,544 Equity Securities: Common stocks $ 884 $ 216 $ (21 ) $ 195 $ 1,079 $ 879 $ 160 $ (23 ) $ 137 $ 1,016 Perpetual preferred stocks 472 31 (3 ) 28 500 472 21 (7 ) 14 486 Total equity securities $ 1,356 $ 247 $ (24 ) $ 223 $ 1,579 $ 1,351 $ 181 $ (30 ) $ 151 $ 1,502 The non-credit related portion of other-than-temporary impairment charges is included in other comprehensive income. Cumulative non-credit charges taken for securities still owned at March 31, 2017 and December 31, 2016 , respectively, were $170 million and $189 million . Gross unrealized gains on such securities at March 31, 2017 and December 31, 2016 were $128 million and $130 million , respectively. Gross unrealized losses on such securities at March 31, 2017 and December 31, 2016 were $2 million and $3 million , respectively. These amounts represent the non-credit other-than-temporary impairment charges recorded in AOCI adjusted for subsequent changes in fair values and relate to residential MBS. The following tables show gross unrealized losses (dollars in millions) on fixed maturities and equity securities by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2017 and December 31, 2016 . 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, 2017 Fixed maturities: U.S. Government and government agencies $ (1 ) $ 152 99 % $ (2 ) $ 8 80 % States, municipalities and political subdivisions (44 ) 1,925 98 % (4 ) 37 90 % Foreign government — 4 100 % — — — % Residential MBS (6 ) 455 99 % (5 ) 188 97 % Commercial MBS (1 ) 71 99 % — — — % Asset-backed securities (14 ) 1,313 99 % (16 ) 512 97 % Corporate and other (57 ) 2,799 98 % (15 ) 298 95 % Total fixed maturities $ (123 ) $ 6,719 98 % $ (42 ) $ 1,043 96 % Equity securities: Common stocks $ (21 ) $ 138 87 % $ — $ — — % Perpetual preferred stocks (2 ) 85 98 % (1 ) 6 86 % Total equity securities $ (23 ) $ 223 91 % $ (1 ) $ 6 86 % December 31, 2016 Fixed maturities: U.S. Government and government agencies $ (1 ) $ 153 99 % $ (2 ) $ 8 80 % States, municipalities and political subdivisions (64 ) 2,289 97 % (5 ) 44 90 % Residential MBS (7 ) 502 99 % (6 ) 162 96 % Commercial MBS (2 ) 121 98 % — — — % Asset-backed securities (29 ) 1,737 98 % (17 ) 634 97 % Corporate and other (93 ) 3,849 98 % (19 ) 312 94 % Total fixed maturities $ (196 ) $ 8,651 98 % $ (49 ) $ 1,160 96 % Equity securities: Common stocks $ (23 ) $ 215 90 % $ — $ — — % Perpetual preferred stocks (6 ) 135 96 % (1 ) 6 86 % Total equity securities $ (29 ) $ 350 92 % $ (1 ) $ 6 86 % At March 31, 2017 , the gross unrealized losses on fixed maturities of $165 million relate to 1,048 securities. Investment grade securities (as determined by nationally recognized rating agencies) represented approximately 84% of the gross unrealized loss and 89% of the fair value. AFG analyzes its MBS securities for other-than-temporary 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 2017 , AFG recorded less than $1 million in other-than-temporary impairment charges related to its residential MBS. In the first three months of 2017 , AFG recorded less than $1 million in other-than-temporary impairment charges related to corporate bonds and other fixed maturities. AFG recorded $3 million in other-than-temporary impairment charges on common stocks in the first three months of 2017 . At March 31, 2017 , the gross unrealized losses on common stocks of $21 million relate to 17 securities, none of which has been in an unrealized loss position for more than 12 months. AFG recorded $6 million in other-than-temporary impairment charges on preferred stocks in the first three months of 2017 . At March 31, 2017 , the gross unrealized losses on preferred stocks of $3 million relate to 13 securities. The one preferred stock that has been in an unrealized loss position for 12 months or more is rated investment grade. Management believes AFG will recover its cost basis 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, 2017 . A progression of the credit portion of other-than-temporary impairments on fixed maturity securities for which the non-credit portion of an impairment has been recognized in other comprehensive income is shown below (in millions): 2017 2016 Balance at January 1 $ 153 $ 160 Additional credit impairments on: Previously impaired securities — 2 Securities without prior impairments — — Reductions due to sales or redemptions (7 ) (2 ) Balance at March 31 $ 146 $ 160 The table below sets forth the scheduled maturities of available for sale fixed maturities as of March 31, 2017 (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 Amount % Maturity One year or less $ 1,038 $ 1,051 3 % After one year through five years 6,034 6,300 17 % After five years through ten years 12,717 12,990 36 % After ten years 4,465 4,554 12 % 24,254 24,895 68 % ABS (average life of approximately 5 years) 6,548 6,592 18 % MBS (average life of approximately 4-1/2 years) 4,643 4,969 14 % Total $ 35,445 $ 36,456 100 % 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, 2017 or December 31, 2016 . Net Unrealized Gain on Marketable Securities In addition to adjusting equity securities and 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, 2017 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 800 $ (280 ) $ 520 Fixed maturities — all other 211 (74 ) 137 Total fixed maturities 1,011 (354 ) 657 Equity securities 223 (78 ) 145 Total investments 1,234 (432 ) 802 Deferred policy acquisition costs — annuity segment (333 ) 117 (216 ) Annuity benefits accumulated (103 ) 36 (67 ) Unearned revenue 15 (5 ) 10 Total net unrealized gain on marketable securities $ 813 $ (284 ) $ 529 December 31, 2016 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 640 $ (224 ) $ 416 Fixed maturities — all other 169 (59 ) 110 Total fixed maturities 809 (283 ) 526 Equity securities 151 (53 ) 98 Total investments 960 (336 ) 624 Deferred policy acquisition costs — annuity segment (273 ) 96 (177 ) Annuity benefits accumulated (78 ) 27 (51 ) Unearned revenue 13 (5 ) 8 Total net unrealized gain on marketable securities $ 622 $ (218 ) $ 404 (*) 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, 2017 2016 Investment income: Fixed maturities $ 389 $ 367 Equity securities 21 19 Equity in earnings of partnerships and similar investments 10 11 Other 20 19 Gross investment income 440 416 Investment expenses (5 ) (5 ) Net investment income $ 435 $ 411 Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments are summarized as follows (in millions): Three months ended March 31, 2017 Three months ended March 31, 2016 Realized gains (losses) Realized gains (losses) Before Impairments Impairments Total Change in Unrealized Before Impairments Impairments Total Change in Unrealized Fixed maturities $ 5 $ — $ 5 $ 202 $ 14 $ (16 ) $ (2 ) $ 453 Equity securities 2 (9 ) (7 ) 72 23 (41 ) (18 ) (23 ) Mortgage loans and other investments 3 — 3 — — — — — Other (*) (1 ) 3 2 (83 ) (3 ) 5 2 (220 ) Total pretax 9 (6 ) 3 191 34 (52 ) (18 ) 210 Tax effects (3 ) 2 (1 ) (66 ) (12 ) 19 7 (74 ) Noncontrolling interests — — — — — 1 1 (2 ) Net of tax and noncontrolling interests $ 6 $ (4 ) $ 2 $ 125 $ 22 $ (32 ) $ (10 ) $ 134 (*) Primarily adjustments to deferred policy acquisition costs and reserves related to the annuity business. Gross realized gains and losses (excluding impairment write-downs and mark-to-market of derivatives) on available for sale fixed maturity and equity security investment transactions included in the statement of cash flows consisted of the following (in millions): Three months ended March 31, 2017 2016 Fixed maturities: Gross gains $ 5 $ 14 Gross losses — (1 ) Equity securities: Gross gains 4 25 Gross losses (2 ) —

Derivatives

Derivatives	3 Months Ended
	Mar. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives As discussed under “ Derivatives ” in Note A — “ Accounting Policies ” to the financial statements, 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, 2017 December 31, 2016 Derivative Balance Sheet Line Asset Liability Asset Liability MBS with embedded derivatives Fixed maturities $ 104 $ — $ 107 $ — Public company warrants Equity securities 4 — 4 — Fixed-indexed annuities (embedded derivative) Annuity benefits accumulated — 1,963 — 1,759 Equity index call options Equity index call options 573 — 492 — Reinsurance contracts (embedded derivative) Other liabilities — 8 — 8 $ 681 $ 1,971 $ 603 $ 1,767 The MBS with embedded derivatives consist primarily of interest-only MBS with interest rates that float inversely with short-term rates. 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 annuities provide policyholders with a crediting rate tied, in part, to the performance of an existing stock market index. AFG attempts to mitigate the risk in the index-based component of these products through the purchase of call options on the appropriate index. AFG receives collateral from its counterparties to support its purchased call option assets. This collateral ( $387 million at March 31, 2017 and $380 million at December 31, 2016 ) 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 change in the fair value of the call option assets will generally offset the economic change in the liabilities from the index participation. Both the index-based component of the annuities and the related call options are considered derivatives. Fluctuations in interest rates and the stock market, among other factors, can cause volatility in the periodic measurement of fair value of the embedded derivative that management believes can be inconsistent with the long-term economics of these products. As discussed under “ Reinsurance ” in Note A to the financial statements, certain reinsurance contracts are considered to contain embedded derivatives. The following table summarizes the gain (loss) 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 2017 and 2016 (in millions): Three months ended March 31, Derivative Statement of Earnings Line 2017 2016 MBS with embedded derivatives Realized gains on securities $ — $ 1 Public company warrants Realized gains on securities — (2 ) Fixed-indexed annuities (embedded derivative) Annuity benefits (147 ) (17 ) Equity index call options Annuity benefits 141 (40 ) Reinsurance contracts (embedded derivative) Net investment income (1 ) (3 ) $ (7 ) $ (61 ) Derivatives Designated and Qualifying as Cash Flow Hedges As of March 31, 2017 , AFG has entered into seven 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 amortize down over each swap’s respective life (the swaps expire between August 2019 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 $1.03 billion at March 31, 2017 compared to $1.08 billion at December 31, 2016 , reflecting the scheduled amortization discussed above. The fair value of the effective portion of the interest rate swaps in an asset position and included in other assets was less than $1 million at March 31, 2017 and $1 million at December 31, 2016 . The fair value of the effective portion of the interest rate swaps in a liability position and included in other liabilities was $24 million at March 31, 2017 and $22 million at December 31, 2016 . 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 $2 million in both the first three months of 2017 and 2016 . There was no ineffectiveness recorded in net earnings during these periods. A collateral receivable supporting these swaps of $60 million at both March 31, 2017 and December 31, 2016 is included in other assets in AFG’s Balance Sheet. Derivative Designated and Qualifying as a Fair Value Hedge In June 2015, AFG entered into an interest rate swap to mitigate the interest rate risk associated with its fixed-rate 9-7/8% Senior Notes due June 2019 by effectively converting the interest rate on those notes to a floating rate of three-month LIBOR plus 8.099% ( 9.2302% at March 31, 2017 ). Since the terms of the interest rate swap match the terms of the hedged debt, changes in the fair value of the interest rate swap are offset by changes in the fair value of the hedged debt attributable to changes in interest rates. The fair value of the interest rate swap (asset of less than $1 million at March 31, 2017 and $1 million at December 31, 2016 ) and the offsetting adjustment to the carrying value of the 9-7/8% Senior Notes are both included in long-term debt on AFG’s Balance Sheet. Accordingly, the net impact on AFG’s current period earnings is that the interest expense associated with the hedged debt is effectively recorded at the floating rate. The net reduction in interest expense from the swap was $1 million for both the first three months of 2017 and 2016 .

Deferred Policy Acquisition Cos

Deferred Policy Acquisition Costs	3 Months Ended
	Mar. 31, 2017
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 Run-off Long-term Care and Life Deferred Deferred Sales Consolidated Costs Costs Inducements PVFP Subtotal Unrealized Total Total Balance at December 31, 2016 $ 238 $ 1,110 $ 110 $ 46 $ 1,266 $ (265 ) $ 1,001 $ 1,239 Additions 139 67 1 — 68 — 68 207 Amortization: Periodic amortization (135 ) (42 ) (6 ) (2 ) (50 ) — (50 ) (185 ) Included in realized gains — 2 — — 2 — 2 2 Foreign currency translation 1 — — — — — — 1 Change in unrealized — — — — — (59 ) (59 ) (59 ) Balance at March 31, 2017 $ 243 $ 1,137 $ 105 $ 44 $ 1,286 $ (324 ) $ 962 $ 1,205 Balance at December 31, 2015 $ 226 $ 1,018 $ 119 $ 55 $ 1,192 $ (234 ) $ 958 $ 1,184 Additions 132 68 5 — 73 — 73 205 Amortization: Periodic amortization (134 ) (25 ) (5 ) (2 ) (32 ) — (32 ) (166 ) Included in realized gains — 2 — — 2 — 2 2 Change in unrealized — — — — — (170 ) (170 ) (170 ) Balance at March 31, 2016 $ 224 $ 1,063 $ 119 $ 53 $ 1,235 $ (404 ) $ 831 $ 1,055 The present value of future profits (“PVFP”) amounts in the table above are net of $136 million and $134 million of accumulated amortization at March 31, 2017 and December 31, 2016 , respectively.

Managed Investment Entities

Managed Investment Entities	3 Months Ended
	Mar. 31, 2017
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 64.4% of the most subordinate debt tranche of sixteen collateralized loan obligation entities or “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 2004 and 2017, 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 particular 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 its CLOs is limited to its investment in the CLOs, which had an aggregate fair value of $230 million (including $160 million invested in the most subordinate tranches) at March 31, 2017 , and $216 million at December 31, 2016 . In March 2017, AFG formed a new CLO, which issued $408 million face amount of liabilities (including $24 million face amount purchased by subsidiaries of AFG). During the first three months of 2016 , AFG subsidiaries purchased $11 million face amount of senior debt and subordinate tranches of existing CLOs for $10 million . During the first three months of 2017 and 2016 , AFG subsidiaries received $4 million and $23 million , respectively, 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, 2017 2016 Investment in CLO tranches at end of period $ 230 $ 250 Gains (losses) on change in fair value of assets/liabilities (a): Assets 5 (1 ) Liabilities (5 ) (12 ) Management fees paid to AFG 4 4 CLO earnings (losses) attributable to AFG shareholders (b) 6 (7 ) (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 $59 million and $75 million at March 31, 2017 and December 31, 2016 . The aggregate unpaid principal balance of the CLOs’ debt exceeded its carrying value by $140 million and $159 million at those dates. The CLO assets include $1 million in loans at both March 31, 2017 and December 31, 2016 , for which the CLOs are not accruing interest because the loans are in default (aggregate unpaid principal balance of $8 million and $10 million at those dates, respectively).

Goodwill and Other Intangibles

Goodwill and Other Intangibles	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles	Goodwill and Other Intangibles There were no changes in the goodwill balance of $199 million during the first three months of 2017 . Included in other assets in AFG’s Balance Sheet is $32 million at March 31, 2017 and $34 million at December 31, 2016 in amortizable intangible assets related to property and casualty insurance acquisitions. These amounts are net of accumulated amortization of $24 million and $25 million , respectively. Amortization of intangibles was $2 million in both the first three months of 2017 and 2016 .

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following (in millions): March 31, 2017 December 31, 2016 Principal Discount and Issue Costs Carrying Value Principal Discount and Issue Costs Carrying Value Direct Senior Obligations of AFG: 9-7/8% Senior Notes due June 2019 $ 350 $ (1 ) $ 349 $ 350 $ (1 ) $ 349 3.50% Senior Notes due August 2026 300 (3 ) 297 300 (3 ) 297 6-3/8% Senior Notes due June 2042 230 (7 ) 223 230 (7 ) 223 5-3/4% Senior Notes due August 2042 125 (4 ) 121 125 (4 ) 121 Other 3 — 3 3 — 3 1,008 (15 ) 993 1,008 (15 ) 993 Direct Subordinated Obligations of AFG: 6-1/4% Subordinated Debentures due September 2054 150 (5 ) 145 150 (5 ) 145 6% Subordinated Debentures due November 2055 150 (5 ) 145 150 (5 ) 145 300 (10 ) 290 300 (10 ) 290 $ 1,308 $ (25 ) $ 1,283 $ 1,308 $ (25 ) $ 1,283 To achieve a desired balance between fixed and variable rate debt, AFG entered into an interest rate swap in June 2015, which effectively converts its 9-7/8% Senior Notes to a floating rate of three-month LIBOR plus 8.099% ( 9.2302% at March 31, 2017 and 9.0624% at December 31, 2016 ). The fair value of the interest rate swap (asset of less than $1 million and $1 million at March 31, 2017 and December 31, 2016 , respectively) and the offsetting adjustment to the carrying value of the notes are both included in the carrying value of the 9-7/8% Senior Notes in the table above. Scheduled principal payments on debt for the balance of 2017 , the subsequent five years and thereafter were as follows: 2017 — none ; 2018 — none ; 2019 — $350 million ; 2020 — none ; 2021 — none ; 2022 — none and thereafter — $958 million . 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, 2017 or December 31, 2016 .

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2017
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 AOCI Beginning Balance Pretax Tax Net of tax Attributable to noncontrolling interests Attributable to shareholders AOCI Ending Balance Three months ended March 31, 2017 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 191 $ (66 ) $ 125 $ — $ 125 Reclassification adjustment for realized (gains) losses included in net earnings (a) — — — — — Total net unrealized gains on securities (b) $ 404 191 (66 ) 125 — 125 $ 529 Net unrealized losses on cash flow hedges (7 ) (2 ) 1 (1 ) — (1 ) (8 ) Foreign currency translation adjustments (15 ) — — — — — (15 ) Pension and other postretirement plans adjustments (7 ) — — — — — (7 ) Total $ 375 $ 189 $ (65 ) $ 124 $ — $ 124 $ 499 Three months ended March 31, 2016 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 192 $ (67 ) $ 125 $ (1 ) $ 124 Reclassification adjustment for realized (gains) losses included in net earnings (a) 18 (7 ) 11 (1 ) 10 Total net unrealized gains on securities $ 332 210 (74 ) 136 (2 ) 134 $ 466 Net unrealized gains on cash flow hedges 1 5 (2 ) 3 — 3 4 Foreign currency translation adjustments (22 ) 3 3 6 — 6 (16 ) Pension and other postretirement plans adjustments (7 ) 1 — 1 — 1 (6 ) Total $ 304 $ 219 $ (73 ) $ 146 $ (2 ) $ 144 $ 448 (a) The reclassification adjustment out of net unrealized gains 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 for income taxes Attributable to noncontrolling interests Net earnings (loss) attributable to noncontrolling interests (b) Includes net unrealized gains of $52 million at both March 31, 2017 and December 31, 2016 related to securities for which only the credit portion of an other-than-temporary impairment has been recorded in earnings. 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 2017 , AFG issued 232,250 shares of restricted Common Stock (fair value of $94.44 per share) under the Stock Incentive Plan. In addition, AFG issued 47,826 shares of Common Stock (fair value of $96.13 per share) in the first quarter of 2017 under the Equity Bonus Plan. AFG did not grant any stock options in the first three months of 2017 . Total compensation expense related to stock incentive plans of AFG and its subsidiaries was $11 million and $8 million in the first three months of 2017 and 2016 , respectively.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following is a reconciliation of income taxes at the statutory rate of 35% to the provision for income taxes as shown in AFG’s Statement of Earnings (dollars in millions): Three months ended March 31, 2017 2016 Amount % of EBT Amount % of EBT Earnings before income taxes (“EBT”) $ 223 $ 156 Income taxes at statutory rate $ 78 35 % $ 55 35 % Effect of: Tax exempt interest (6 ) (3 %) (7 ) (4 %) Stock-based compensation (6 ) (3 %) — — % Change in valuation allowance (2 ) (1 %) 1 1 % Subsidiaries not in AFG’s tax return — — % 1 — % Other 4 2 % 2 1 % Provision for income taxes as shown in the statement of earnings $ 68 30 % $ 52 33 % The favorable impact of stock-based compensation on AFG’s effective tax rate in the first three months of 2017 reflects the high volume of employee stock option exercises during that period, including the impact of the increase in the market price of AFG Common Stock. During the first three months of 2017 , there were no material changes to AFG’s liability for uncertain tax positions.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies There have been no significant changes to the matters discussed and referred to in Note M — “Contingencies” of AFG’s 2016 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, as well as contingencies related to the sale of substantially all of AFG’s run-off long-term care insurance business.

Insurance

Insurance	3 Months Ended
	Mar. 31, 2017
Insurance [Abstract]
Unpaid Losses and Loss Adjustment Expenses	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 2017 and 2016 (in millions): Three months ended March 31, 2017 2016 Balance at beginning of year $ 8,563 $ 8,127 Less reinsurance recoverables, net of allowance 2,302 2,201 Net liability at beginning of year 6,261 5,926 Provision for losses and LAE occurring in the current period 637 609 Net increase (decrease) in the provision for claims of prior years (28 ) (28 ) Total losses and LAE incurred 609 581 Payments for losses and LAE of: Current year (84 ) (80 ) Prior years (470 ) (467 ) Total payments (554 ) (547 ) Foreign currency translation and other 8 11 Net liability at end of period 6,324 5,971 Add back reinsurance recoverables, net of allowance 2,297 2,137 Gross unpaid losses and LAE included in the balance sheet at end of period $ 8,621 $ 8,108 The net decrease in the provision for claims of prior years during the first three months of 2017 reflects (i) lower than expected losses in the crop and equine operations and lower than expected claim severity in the property and inland marine business (all within the Property and transportation sub-segment), (ii) lower than anticipated claim severity and frequency in the workers’ compensation businesses and lower than anticipated claim severity at Neon (all within the Specialty casualty sub-segment) and (iii) lower than anticipated claim severity in the fidelity business and lower than expected claim frequency and severity in the surety business (all within the Specialty financial sub-segment). This favorable development was partially offset by (i) higher than anticipated claim severity in the ocean marine business (within the Property and transportation sub-segment), (ii) higher than anticipated claim severity in the targeted markets business and higher than anticipated claim severity and frequency in the excess and surplus lines business (all within the Specialty casualty sub-segment) and (iii) an adjustment to the deferred gain on the retroactive reinsurance transaction entered into in connection with the sale of businesses in 1998 (included in Other specialty sub-segment). The net decrease in the provision for claims of prior years during the first three months of 2016 reflects (i) lower than expected losses in the crop operations and lower than expected claim severity in the property and inland marine and trucking businesses (all within the Property and transportation sub-segment), (ii) lower than anticipated claim severity in workers’ compensation business and in directors and officers liability insurance (all within the Specialty casualty sub-segment) and (iii) lower than anticipated claim severity in the fidelity business and lower than expected claim frequency and severity in the surety business (all within the Specialty financial sub-segment). This favorable development was partially offset by (i) higher than anticipated claim frequency in the ocean marine business (within the Property and transportation sub-segment), (ii) adverse reserve development at Neon and higher than anticipated severity in contractor claims (all within the Specialty casualty sub-segment) and (iii) higher than anticipated claim frequency in the financial institutions business (within the Specialty financial sub-segment).

Subsequent Event

Subsequent Event	3 Months Ended
	Mar. 31, 2017
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On May 3, 2017, AFG announced that its Board of Directors declared a special cash dividend of $1.50 per share of American Financial Group Common Stock. The dividend is payable on May 25, 2017 to shareholders of record on May 15, 2017. The aggregate amount of this special dividend will be approximately $132 million .

Accounting Policies (Policies)

Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2017
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, 2017 , 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	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 significant nonrecurring fair value measurements in the first three months of 2017 .
Investments	Investments Fixed maturity and equity securities classified as “available for sale” are reported at fair value with unrealized gains and losses included in accumulated other comprehensive income (“AOCI”) in AFG’s Balance Sheet. Fixed maturity and equity 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. In January 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-01, which, among other things, will require all equity securities currently classified as “available for sale” to be reported at fair value, with holding gains and losses recognized in net income, instead of AOCI. AFG will be required to adopt this guidance effective January 1, 2018. Premiums and discounts on fixed maturity securities are amortized using the 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. Gains or losses on securities are determined on the specific identification basis. When a decline in the value of a specific investment is considered to be other-than-temporary at the balance sheet date, a provision for impairment is charged to earnings (included in realized gains (losses) on securities) and the cost basis of that investment is reduced. If management can assert that it does not intend to sell an impaired fixed maturity security and it is not more likely than not that it will have to sell the security before recovery of its amortized cost basis, then the other-than-temporary impairment 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 of an other-than-temporary impairment 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 impairment 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 charge to earnings is recorded to reduce the amortized cost of that security to fair value.
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 MBS) and (ii) the equity-based component of certain annuity products (included in annuity benefits accumulated) and related equity index call 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. Any hedge ineffectiveness is immediately recorded in current period 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. For derivatives that are designated and qualify as highly effective fair value hedges, changes in the fair value of the derivative, along with changes in the fair value of the hedged item attributable to the hedged risk, are recognized in current period earnings. AFG has entered into an interest rate swap that qualifies as a highly effective fair value hedge to mitigate the interest rate risk associated with fixed-rate long-term debt by economically converting certain fixed-rate debt obligations to floating-rate obligations. Since the terms of the swap match the terms of the hedged debt, changes in the fair value of the swap are offset by changes in the fair value of the hedged debt attributable to changes in interest rates. Accordingly, the net impact on AFG’s current period earnings is that the interest expense associated with the hedged debt is effectively recorded at the floating rate.
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, long-term care 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 the 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 expense and decreases for policy charges are credited to other income. 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 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	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 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 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	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.
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.
Noncontrolling Interests	Noncontrolling Interests For balance sheet purposes, noncontrolling interests represents 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.
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. 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. See Note K — “ Shareholders’ Equity ” for further information. In the fourth quarter of 2016, AFG adopted ASU 2016-09, which, among other things, requires excess tax benefits or deficiencies for share-based payments to be recorded through income tax expense in the statement of earnings instead of directly to capital surplus (as required under the previous guidance). In addition, under the new guidance, AFG elected to account for forfeitures of awards when they occur rather than accruing expense based on an estimate of expected forfeitures (as required under the previous guidance). The resulting cumulative effect of accounting change of less than $1 million was recorded directly to retained earnings on January 1, 2016.
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 2017 and 2016 — 2.1 million and 1.6 million , respectively. AFG’s weighted average diluted shares outstanding for the first three months of 2016 excludes 0.8 million anti-dilutive potential common shares related to stock compensation plans. There were no anti-dilutive potential common shares for the first three months of 2017 .
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 and property and equipment. “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. Effective October 1, 2016, AFG early adopted (on a retrospective basis) ASU 2016-15, which addresses the diversity in practice in how certain cash receipts and cash payments are presented in the statement of cash flows. Among other things, this guidance requires proceeds received from the settlement of corporate-owned life insurance policies to be classified as cash inflows from investing activities and allows premiums paid for policies to be reported as cash outflows either from investing activities or operating activities. AFG has elected to show all corporate-owned life insurance activity in investing activities. Prior to adoption of this guidance, AFG accounted for these transactions as operating activities. In addition, ASU 2016-15 clarifies when distributions received from investees accounted under the equity method should be accounted for as a cash inflow from operating activities or as a cash inflow from investing activities. AFG had previously accounted for all distributions from investments accounted for under the equity method as investing activities. The new guidance solely related to the presentation of certain transactions in the statement of cash flows. Accordingly, adoption of this guidance did not impact AFG’s results of operations or financial position.
Revenue Recognition Guidance Effective in 2018	Revenue Recognition Guidance Effective in 2018 In May 2014, the FASB issued ASU 2014-09, which requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Revenue is recognized when (or as) the entity satisfies a performance obligation under the contract. The new guidance also updates the accounting for certain costs associated with obtaining and fulfilling contracts with customers and requires disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Revenue recognition for insurance contracts and financial instruments, which are AFG’s primary sources of revenue, is excluded from the scope of the new guidance. AFG will adopt the new guidance effective January 1, 2018. Because the new guidance does not apply to the vast majority of AFG’s business, management does not expect the adoption of this guidance to have a material impact on AFG’s results of operations or financial position. Based on implementation efforts to date, management believes that the new standard would only have applied to 2% of AFG’s 2016 consolidated revenues.

Segments of Operations (Tables)

Segments of Operations (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 Revenues Property and casualty insurance: Premiums earned: Specialty Property and transportation $ 342 $ 339 Specialty casualty 508 502 Specialty financial 147 132 Other specialty 25 25 Total premiums earned 1,022 998 Net investment income 86 83 Other income (a) 16 3 Total property and casualty insurance 1,124 1,084 Annuity: Net investment income 347 315 Other income 27 26 Total annuity 374 341 Run-off long-term care and life 12 12 Other 63 56 Total revenues before realized gains (losses) 1,573 1,493 Realized gains (losses) on securities 3 (18 ) Total revenues $ 1,576 $ 1,475 Earnings Before Income Taxes Property and casualty insurance: Underwriting: Specialty Property and transportation $ 43 $ 32 Specialty casualty 15 29 Specialty financial 22 23 Other specialty (1 ) 2 Other lines (1 ) 1 Total underwriting 78 87 Investment and other income, net (a) 93 75 Total property and casualty insurance 171 162 Annuity 96 53 Run-off long-term care and life — (1 ) Other (b) (47 ) (40 ) Total earnings before realized gains (losses) and income taxes 220 174 Realized gains (losses) on securities 3 (18 ) Total earnings before income taxes $ 223 $ 156 (a) Includes pretax income of $13 million (before noncontrolling interest) from the sale of a hotel in the first quarter of 2017. (b) Includes holding company interest and expenses.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 Assets: Available for sale (“AFS”) fixed maturities: U.S. Government and government agencies $ 122 $ 158 $ 8 $ 288 States, municipalities and political subdivisions — 6,758 143 6,901 Foreign government — 138 — 138 Residential MBS — 3,541 175 3,716 Commercial MBS — 1,224 29 1,253 Asset-backed securities (“ABS”) — 5,998 594 6,592 Corporate and other 30 16,710 828 17,568 Total AFS fixed maturities 152 34,527 1,777 36,456 Trading fixed maturities 26 333 — 359 Equity securities — AFS and trading 1,383 81 173 1,637 Assets of managed investment entities (“MIE”) 896 4,409 26 5,331 Variable annuity assets (separate accounts) (*) — 614 — 614 Equity index call options — 573 — 573 Other assets — derivatives — — — — Total assets accounted for at fair value $ 2,457 $ 40,537 $ 1,976 $ 44,970 Liabilities: Liabilities of managed investment entities $ 857 $ 4,219 $ 25 $ 5,101 Derivatives in annuity benefits accumulated — — 1,963 1,963 Derivatives in long-term debt — — — — Other liabilities — derivatives — 32 — 32 Total liabilities accounted for at fair value $ 857 $ 4,251 $ 1,988 $ 7,096 December 31, 2016 Assets: Available for sale fixed maturities: U.S. Government and government agencies $ 133 $ 174 $ 8 $ 315 States, municipalities and political subdivisions — 6,641 140 6,781 Foreign government — 136 — 136 Residential MBS — 3,445 190 3,635 Commercial MBS — 1,468 25 1,493 Asset-backed securities — 5,475 484 5,959 Corporate and other 29 15,484 712 16,225 Total AFS fixed maturities 162 32,823 1,559 34,544 Trading fixed maturities 30 329 — 359 Equity securities — AFS and trading 1,305 79 174 1,558 Assets of managed investment entities 380 4,356 29 4,765 Variable annuity assets (separate accounts) (*) — 600 — 600 Equity index call options — 492 — 492 Other assets — derivatives — 1 — 1 Total assets accounted for at fair value $ 1,877 $ 38,680 $ 1,762 $ 42,319 Liabilities: Liabilities of managed investment entities $ 363 $ 4,158 $ 28 $ 4,549 Derivatives in annuity benefits accumulated — — 1,759 1,759 Derivatives in long-term debt — (1 ) — (1 ) Other liabilities — derivatives — 30 — 30 Total liabilities accounted for at fair value $ 363 $ 4,187 $ 1,787 $ 6,337 (*) 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 embedded derivatives. See Note F — “ Derivatives .” Unobservable Input Range Adjustment for insurance subsidiary’s credit risk 0.2% – 2.8% over the risk free rate Risk margin for uncertainty in cash flows 0.68% reduction in the discount rate Surrenders 3% – 21% of indexed account value Partial surrenders 2% – 10% of indexed account value Annuitizations 0.1% – 1% of indexed account value Deaths 1.5% – 8.0% of indexed account value Budgeted option costs 2.4% – 3.6% 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 2017 and 2016 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, 2016 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2017 AFS fixed maturities: U.S. government agency $ 8 $ — $ — $ — $ — $ — $ — $ 8 State and municipal 140 — 3 — — — — 143 Residential MBS 190 1 — 1 (8 ) 7 (16 ) 175 Commercial MBS 25 — — — — 4 — 29 Asset-backed securities 484 — — 104 (11 ) 17 — 594 Corporate and other 712 1 4 120 (38 ) 29 — 828 Total AFS fixed maturities 1,559 2 7 225 (57 ) 57 (16 ) 1,777 Equity securities 174 (6 ) 7 12 — — (14 ) 173 Assets of MIE 29 (1 ) — 2 — — (4 ) 26 Total Level 3 assets $ 1,762 $ (5 ) $ 14 $ 239 $ (57 ) $ 57 $ (34 ) $ 1,976 Embedded derivatives $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total Level 3 liabilities (*) $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2015 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2016 AFS fixed maturities: U.S. government agency $ 15 $ — $ — $ — $ — $ — $ — $ 15 State and municipal 89 — 3 — — — — 92 Residential MBS 224 1 — — (7 ) 11 (16 ) 213 Commercial MBS 39 — — — (1 ) — — 38 Asset-backed securities 470 — (6 ) 4 (8 ) 41 — 501 Corporate and other 633 (2 ) 15 86 (7 ) 5 — 730 Total AFS fixed maturities 1,470 (1 ) 12 90 (23 ) 57 (16 ) 1,589 Equity securities 140 (17 ) 8 12 — 15 — 158 Assets of MIE 26 (2 ) — — — — — 24 Total Level 3 assets $ 1,636 $ (20 ) $ 20 $ 102 $ (23 ) $ 72 $ (16 ) $ 1,771 Embedded derivatives $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) Total Level 3 liabilities (*) $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) (*) As discussed previously, 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 2017 and 2016 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, 2016 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2017 AFS fixed maturities: U.S. government agency $ 8 $ — $ — $ — $ — $ — $ — $ 8 State and municipal 140 — 3 — — — — 143 Residential MBS 190 1 — 1 (8 ) 7 (16 ) 175 Commercial MBS 25 — — — — 4 — 29 Asset-backed securities 484 — — 104 (11 ) 17 — 594 Corporate and other 712 1 4 120 (38 ) 29 — 828 Total AFS fixed maturities 1,559 2 7 225 (57 ) 57 (16 ) 1,777 Equity securities 174 (6 ) 7 12 — — (14 ) 173 Assets of MIE 29 (1 ) — 2 — — (4 ) 26 Total Level 3 assets $ 1,762 $ (5 ) $ 14 $ 239 $ (57 ) $ 57 $ (34 ) $ 1,976 Embedded derivatives $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total Level 3 liabilities (*) $ (1,759 ) $ (147 ) $ — $ (79 ) $ 22 $ — $ — $ (1,963 ) Total realized/unrealized gains (losses) included in Balance at December 31, 2015 Net income Other comprehensive income (loss) Purchases and issuances Sales and settlements Transfer into Level 3 Transfer out of Level 3 Balance at March 31, 2016 AFS fixed maturities: U.S. government agency $ 15 $ — $ — $ — $ — $ — $ — $ 15 State and municipal 89 — 3 — — — — 92 Residential MBS 224 1 — — (7 ) 11 (16 ) 213 Commercial MBS 39 — — — (1 ) — — 38 Asset-backed securities 470 — (6 ) 4 (8 ) 41 — 501 Corporate and other 633 (2 ) 15 86 (7 ) 5 — 730 Total AFS fixed maturities 1,470 (1 ) 12 90 (23 ) 57 (16 ) 1,589 Equity securities 140 (17 ) 8 12 — 15 — 158 Assets of MIE 26 (2 ) — — — — — 24 Total Level 3 assets $ 1,636 $ (20 ) $ 20 $ 102 $ (23 ) $ 72 $ (16 ) $ 1,771 Embedded derivatives $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) Total Level 3 liabilities (*) $ (1,369 ) $ (17 ) $ — $ (82 ) $ 18 $ — $ — $ (1,450 ) (*) As discussed previously, 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, 2017 Financial assets: Cash and cash equivalents $ 1,890 $ 1,890 $ 1,890 $ — $ — Mortgage loans 1,159 1,158 — — 1,158 Policy loans 190 190 — — 190 Total financial assets not accounted for at fair value $ 3,239 $ 3,238 $ 1,890 $ — $ 1,348 Financial liabilities: Annuity benefits accumulated (*) $ 30,799 $ 29,997 $ — $ — $ 29,997 Long-term debt 1,283 1,382 — 1,379 3 Total financial liabilities not accounted for at fair value $ 32,082 $ 31,379 $ — $ 1,379 $ 30,000 December 31, 2016 Financial assets: Cash and cash equivalents $ 2,107 $ 2,107 $ 2,107 $ — $ — Mortgage loans 1,147 1,146 — — 1,146 Policy loans 192 192 — — 192 Total financial assets not accounted for at fair value $ 3,446 $ 3,445 $ 2,107 $ — $ 1,338 Financial liabilities: Annuity benefits accumulated (*) $ 29,703 $ 28,932 $ — $ — $ 28,932 Long-term debt 1,284 1,356 — 1,353 3 Total financial liabilities not accounted for at fair value $ 30,987 $ 30,288 $ — $ 1,353 $ 28,935 (*) Excludes $203 million and $204 million of life contingent annuities in the payout phase at March 31, 2017 and December 31, 2016 , respectively.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Available for sale fixed maturities and equity securities	Available for sale fixed maturities and equity securities at March 31, 2017 and December 31, 2016 , consisted of the following (in millions): March 31, 2017 December 31, 2016 Amortized Cost Gross Unrealized Net Unrealized Fair Value Amortized Cost Gross Unrealized Net Unrealized Fair Value Gains Losses Gains Losses Fixed maturities: U.S. Government and government agencies $ 289 $ 2 $ (3 ) $ (1 ) $ 288 $ 315 $ 3 $ (3 ) $ — $ 315 States, municipalities and political subdivisions 6,736 213 (48 ) 165 6,901 6,650 200 (69 ) 131 6,781 Foreign government 133 5 — 5 138 131 5 — 5 136 Residential MBS 3,432 295 (11 ) 284 3,716 3,367 281 (13 ) 268 3,635 Commercial MBS 1,211 43 (1 ) 42 1,253 1,446 49 (2 ) 47 1,493 Asset-backed securities 6,548 74 (30 ) 44 6,592 5,962 43 (46 ) (3 ) 5,959 Corporate and other 17,096 544 (72 ) 472 17,568 15,864 473 (112 ) 361 16,225 Total fixed maturities $ 35,445 $ 1,176 $ (165 ) $ 1,011 $ 36,456 $ 33,735 $ 1,054 $ (245 ) $ 809 $ 34,544 Equity Securities: Common stocks $ 884 $ 216 $ (21 ) $ 195 $ 1,079 $ 879 $ 160 $ (23 ) $ 137 $ 1,016 Perpetual preferred stocks 472 31 (3 ) 28 500 472 21 (7 ) 14 486 Total equity securities $ 1,356 $ 247 $ (24 ) $ 223 $ 1,579 $ 1,351 $ 181 $ (30 ) $ 151 $ 1,502
Available for sale securities in a continuous unrealized loss position	The following tables show gross unrealized losses (dollars in millions) on fixed maturities and equity securities by investment category and length of time that individual securities have been in a continuous unrealized loss position at March 31, 2017 and December 31, 2016 . 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, 2017 Fixed maturities: U.S. Government and government agencies $ (1 ) $ 152 99 % $ (2 ) $ 8 80 % States, municipalities and political subdivisions (44 ) 1,925 98 % (4 ) 37 90 % Foreign government — 4 100 % — — — % Residential MBS (6 ) 455 99 % (5 ) 188 97 % Commercial MBS (1 ) 71 99 % — — — % Asset-backed securities (14 ) 1,313 99 % (16 ) 512 97 % Corporate and other (57 ) 2,799 98 % (15 ) 298 95 % Total fixed maturities $ (123 ) $ 6,719 98 % $ (42 ) $ 1,043 96 % Equity securities: Common stocks $ (21 ) $ 138 87 % $ — $ — — % Perpetual preferred stocks (2 ) 85 98 % (1 ) 6 86 % Total equity securities $ (23 ) $ 223 91 % $ (1 ) $ 6 86 % December 31, 2016 Fixed maturities: U.S. Government and government agencies $ (1 ) $ 153 99 % $ (2 ) $ 8 80 % States, municipalities and political subdivisions (64 ) 2,289 97 % (5 ) 44 90 % Residential MBS (7 ) 502 99 % (6 ) 162 96 % Commercial MBS (2 ) 121 98 % — — — % Asset-backed securities (29 ) 1,737 98 % (17 ) 634 97 % Corporate and other (93 ) 3,849 98 % (19 ) 312 94 % Total fixed maturities $ (196 ) $ 8,651 98 % $ (49 ) $ 1,160 96 % Equity securities: Common stocks $ (23 ) $ 215 90 % $ — $ — — % Perpetual preferred stocks (6 ) 135 96 % (1 ) 6 86 % Total equity securities $ (29 ) $ 350 92 % $ (1 ) $ 6 86 %
Roll forward of cumulative credit portion of other-than-temporary impairments on fixed maturity securities	A progression of the credit portion of other-than-temporary impairments on fixed maturity securities for which the non-credit portion of an impairment has been recognized in other comprehensive income is shown below (in millions): 2017 2016 Balance at January 1 $ 153 $ 160 Additional credit impairments on: Previously impaired securities — 2 Securities without prior impairments — — Reductions due to sales or redemptions (7 ) (2 ) Balance at March 31 $ 146 $ 160
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, 2017 (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 Amount % Maturity One year or less $ 1,038 $ 1,051 3 % After one year through five years 6,034 6,300 17 % After five years through ten years 12,717 12,990 36 % After ten years 4,465 4,554 12 % 24,254 24,895 68 % ABS (average life of approximately 5 years) 6,548 6,592 18 % MBS (average life of approximately 4-1/2 years) 4,643 4,969 14 % Total $ 35,445 $ 36,456 100 %
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, 2017 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 800 $ (280 ) $ 520 Fixed maturities — all other 211 (74 ) 137 Total fixed maturities 1,011 (354 ) 657 Equity securities 223 (78 ) 145 Total investments 1,234 (432 ) 802 Deferred policy acquisition costs — annuity segment (333 ) 117 (216 ) Annuity benefits accumulated (103 ) 36 (67 ) Unearned revenue 15 (5 ) 10 Total net unrealized gain on marketable securities $ 813 $ (284 ) $ 529 December 31, 2016 Net unrealized gain on: Fixed maturities — annuity segment (*) $ 640 $ (224 ) $ 416 Fixed maturities — all other 169 (59 ) 110 Total fixed maturities 809 (283 ) 526 Equity securities 151 (53 ) 98 Total investments 960 (336 ) 624 Deferred policy acquisition costs — annuity segment (273 ) 96 (177 ) Annuity benefits accumulated (78 ) 27 (51 ) Unearned revenue 13 (5 ) 8 Total net unrealized gain on marketable securities $ 622 $ (218 ) $ 404 (*) 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, 2017 2016 Investment income: Fixed maturities $ 389 $ 367 Equity securities 21 19 Equity in earnings of partnerships and similar investments 10 11 Other 20 19 Gross investment income 440 416 Investment expenses (5 ) (5 ) Net investment income $ 435 $ 411
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) related to fixed maturity and equity security investments are summarized as follows (in millions): Three months ended March 31, 2017 Three months ended March 31, 2016 Realized gains (losses) Realized gains (losses) Before Impairments Impairments Total Change in Unrealized Before Impairments Impairments Total Change in Unrealized Fixed maturities $ 5 $ — $ 5 $ 202 $ 14 $ (16 ) $ (2 ) $ 453 Equity securities 2 (9 ) (7 ) 72 23 (41 ) (18 ) (23 ) Mortgage loans and other investments 3 — 3 — — — — — Other (*) (1 ) 3 2 (83 ) (3 ) 5 2 (220 ) Total pretax 9 (6 ) 3 191 34 (52 ) (18 ) 210 Tax effects (3 ) 2 (1 ) (66 ) (12 ) 19 7 (74 ) Noncontrolling interests — — — — — 1 1 (2 ) Net of tax and noncontrolling interests $ 6 $ (4 ) $ 2 $ 125 $ 22 $ (32 ) $ (10 ) $ 134 (*) Primarily adjustments to deferred policy acquisition costs and reserves related to the annuity business.
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 and equity security investment transactions included in the statement of cash flows consisted of the following (in millions): Three months ended March 31, 2017 2016 Fixed maturities: Gross gains $ 5 $ 14 Gross losses — (1 ) Equity securities: Gross gains 4 25 Gross losses (2 ) —

Derivatives (Tables)

Derivatives (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 December 31, 2016 Derivative Balance Sheet Line Asset Liability Asset Liability MBS with embedded derivatives Fixed maturities $ 104 $ — $ 107 $ — Public company warrants Equity securities 4 — 4 — Fixed-indexed annuities (embedded derivative) Annuity benefits accumulated — 1,963 — 1,759 Equity index call options Equity index call options 573 — 492 — Reinsurance contracts (embedded derivative) Other liabilities — 8 — 8 $ 681 $ 1,971 $ 603 $ 1,767
Summary of gain (loss) included in the Statement of Earnings for changes in the fair value of derivatives	The following table summarizes the gain (loss) 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 2017 and 2016 (in millions): Three months ended March 31, Derivative Statement of Earnings Line 2017 2016 MBS with embedded derivatives Realized gains on securities $ — $ 1 Public company warrants Realized gains on securities — (2 ) Fixed-indexed annuities (embedded derivative) Annuity benefits (147 ) (17 ) Equity index call options Annuity benefits 141 (40 ) Reinsurance contracts (embedded derivative) Net investment income (1 ) (3 ) $ (7 ) $ (61 )

Deferred Policy Acquisition C28

Deferred Policy Acquisition Costs (Tables)	3 Months Ended
	Mar. 31, 2017
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 Run-off Long-term Care and Life Deferred Deferred Sales Consolidated Costs Costs Inducements PVFP Subtotal Unrealized Total Total Balance at December 31, 2016 $ 238 $ 1,110 $ 110 $ 46 $ 1,266 $ (265 ) $ 1,001 $ 1,239 Additions 139 67 1 — 68 — 68 207 Amortization: Periodic amortization (135 ) (42 ) (6 ) (2 ) (50 ) — (50 ) (185 ) Included in realized gains — 2 — — 2 — 2 2 Foreign currency translation 1 — — — — — — 1 Change in unrealized — — — — — (59 ) (59 ) (59 ) Balance at March 31, 2017 $ 243 $ 1,137 $ 105 $ 44 $ 1,286 $ (324 ) $ 962 $ 1,205 Balance at December 31, 2015 $ 226 $ 1,018 $ 119 $ 55 $ 1,192 $ (234 ) $ 958 $ 1,184 Additions 132 68 5 — 73 — 73 205 Amortization: Periodic amortization (134 ) (25 ) (5 ) (2 ) (32 ) — (32 ) (166 ) Included in realized gains — 2 — — 2 — 2 2 Change in unrealized — — — — — (170 ) (170 ) (170 ) Balance at March 31, 2016 $ 224 $ 1,063 $ 119 $ 53 $ 1,235 $ (404 ) $ 831 $ 1,055

Managed Investment Entities (Ta

Managed Investment Entities (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 Investment in CLO tranches at end of period $ 230 $ 250 Gains (losses) on change in fair value of assets/liabilities (a): Assets 5 (1 ) Liabilities (5 ) (12 ) Management fees paid to AFG 4 4 CLO earnings (losses) attributable to AFG shareholders (b) 6 (7 ) (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, 2017
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	Long-term debt consisted of the following (in millions): March 31, 2017 December 31, 2016 Principal Discount and Issue Costs Carrying Value Principal Discount and Issue Costs Carrying Value Direct Senior Obligations of AFG: 9-7/8% Senior Notes due June 2019 $ 350 $ (1 ) $ 349 $ 350 $ (1 ) $ 349 3.50% Senior Notes due August 2026 300 (3 ) 297 300 (3 ) 297 6-3/8% Senior Notes due June 2042 230 (7 ) 223 230 (7 ) 223 5-3/4% Senior Notes due August 2042 125 (4 ) 121 125 (4 ) 121 Other 3 — 3 3 — 3 1,008 (15 ) 993 1,008 (15 ) 993 Direct Subordinated Obligations of AFG: 6-1/4% Subordinated Debentures due September 2054 150 (5 ) 145 150 (5 ) 145 6% Subordinated Debentures due November 2055 150 (5 ) 145 150 (5 ) 145 300 (10 ) 290 300 (10 ) 290 $ 1,308 $ (25 ) $ 1,283 $ 1,308 $ (25 ) $ 1,283

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2017
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 AOCI Beginning Balance Pretax Tax Net of tax Attributable to noncontrolling interests Attributable to shareholders AOCI Ending Balance Three months ended March 31, 2017 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 191 $ (66 ) $ 125 $ — $ 125 Reclassification adjustment for realized (gains) losses included in net earnings (a) — — — — — Total net unrealized gains on securities (b) $ 404 191 (66 ) 125 — 125 $ 529 Net unrealized losses on cash flow hedges (7 ) (2 ) 1 (1 ) — (1 ) (8 ) Foreign currency translation adjustments (15 ) — — — — — (15 ) Pension and other postretirement plans adjustments (7 ) — — — — — (7 ) Total $ 375 $ 189 $ (65 ) $ 124 $ — $ 124 $ 499 Three months ended March 31, 2016 Net unrealized gains on securities: Unrealized holding gains on securities arising during the period $ 192 $ (67 ) $ 125 $ (1 ) $ 124 Reclassification adjustment for realized (gains) losses included in net earnings (a) 18 (7 ) 11 (1 ) 10 Total net unrealized gains on securities $ 332 210 (74 ) 136 (2 ) 134 $ 466 Net unrealized gains on cash flow hedges 1 5 (2 ) 3 — 3 4 Foreign currency translation adjustments (22 ) 3 3 6 — 6 (16 ) Pension and other postretirement plans adjustments (7 ) 1 — 1 — 1 (6 ) Total $ 304 $ 219 $ (73 ) $ 146 $ (2 ) $ 144 $ 448 (a) The reclassification adjustment out of net unrealized gains 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 for income taxes Attributable to noncontrolling interests Net earnings (loss) attributable to noncontrolling interests (b) Includes net unrealized gains of $52 million at both March 31, 2017 and December 31, 2016 related to securities for which only the credit portion of an other-than-temporary impairment has been recorded in earnings.

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2017
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 35% to the provision for income taxes as shown in AFG’s Statement of Earnings (dollars in millions): Three months ended March 31, 2017 2016 Amount % of EBT Amount % of EBT Earnings before income taxes (“EBT”) $ 223 $ 156 Income taxes at statutory rate $ 78 35 % $ 55 35 % Effect of: Tax exempt interest (6 ) (3 %) (7 ) (4 %) Stock-based compensation (6 ) (3 %) — — % Change in valuation allowance (2 ) (1 %) 1 1 % Subsidiaries not in AFG’s tax return — — % 1 — % Other 4 2 % 2 1 % Provision for income taxes as shown in the statement of earnings $ 68 30 % $ 52 33 %

Insurance (Tables)

Insurance (Tables)	3 Months Ended
	Mar. 31, 2017
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 2017 and 2016 (in millions): Three months ended March 31, 2017 2016 Balance at beginning of year $ 8,563 $ 8,127 Less reinsurance recoverables, net of allowance 2,302 2,201 Net liability at beginning of year 6,261 5,926 Provision for losses and LAE occurring in the current period 637 609 Net increase (decrease) in the provision for claims of prior years (28 ) (28 ) Total losses and LAE incurred 609 581 Payments for losses and LAE of: Current year (84 ) (80 ) Prior years (470 ) (467 ) Total payments (554 ) (547 ) Foreign currency translation and other 8 11 Net liability at end of period 6,324 5,971 Add back reinsurance recoverables, net of allowance 2,297 2,137 Gross unpaid losses and LAE included in the balance sheet at end of period $ 8,621 $ 8,108

Accounting Policies - Narrative

Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jan. 01, 2016
Significant Accounting Policies [Line Items]
Weighted average common shares adjustment related to stock-based compensation (shares)	2,100,000	1,600,000
Anti-dilutive potential common shares related to stock-based compensation plans (shares)	0	800,000
Maturities of short term investments	3 months
Retained Earnings | Maximum
Significant Accounting Policies [Line Items]
Cumulative effect of accounting change			$ 1

Accounting Policies - Narrati35

Accounting Policies - Narrative on Revenue Recognition Guidance (Details)	3 Months Ended
	Mar. 31, 2017
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Expected effect on consolidated revenues under new revenue recognition guidance effective in 2018	2.00%

Acquisition of Business - Narra

Acquisition of Business - Narrative on Acquisition of Subsidiary (Details) - National Interstate $ / shares in Units, $ in Millions	Nov. 10, 2016USD ($)$ / shares
Business Acquisition
Percentage ownership of National Interstate by noncontrolling owners prior to acquisition	49.00%
Payments to acquire additional interest in subsidiaries | $	$ 315
Acquisition price per share (USD per share)	$ 32
Cash dividend paid (USD per share)	$ 0.50

Segments of Operations - Narrat

Segments of Operations - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)segment
Segment Reporting Information [Line Items]
Number of segments | segment	4
Property and Casualty Insurance | Real Estate Investment
Segment Reporting Information [Line Items]
Pretax income from the sale of a hotel | $	$ 13

Segments of Operations - Revenu

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Total premiums earned		$ 1,022	$ 998
Net investment income		435	411
Other income		59	46
Revenues before realized gains (losses)		1,573	1,493
Realized gains (losses) on securities		3	(18)
Total revenues		1,576	1,475
Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned		1,022	998
Net investment income		86	83
Other income	[1]	16	3
Revenues before realized gains (losses)		1,124	1,084
Annuity
Segment Reporting Information [Line Items]
Net investment income		347	315
Other income		27	26
Revenues before realized gains (losses)		374	341
Run-off Long-term Care and Life
Segment Reporting Information [Line Items]
Revenues before realized gains (losses)		12	12
Other
Segment Reporting Information [Line Items]
Revenues before realized gains (losses)		63	56
Specialty Property and transportation | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned		342	339
Specialty casualty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned		508	502
Specialty financial | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned		147	132
Other specialty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Total premiums earned		$ 25	$ 25
[1]	Includes pretax income of $13 million (before noncontrolling interest) from the sale of a hotel in the first quarter of 2017.

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, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes		$ 220	$ 174
Realized gains (losses) on securities		3	(18)
Earnings before income taxes		223	156
Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		78	87
Investment and other income, net	[1]	93	75
Earnings before realized gains (losses) and income taxes		171	162
Annuity
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes		96	53
Run-off Long-term Care and Life
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes		0	(1)
Other
Segment Reporting Information [Line Items]
Earnings before realized gains (losses) and income taxes	[2]	(47)	(40)
Specialty Property and transportation | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		43	32
Specialty casualty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		15	29
Specialty financial | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		22	23
Other specialty | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		(1)	2
Other Lines | Property and Casualty Insurance
Segment Reporting Information [Line Items]
Property and casualty insurance underwriting		$ (1)	$ 1
[1]	Includes pretax income of $13 million (before noncontrolling interest) from the sale of a hotel in the first quarter of 2017.
[2]	Includes holding company interest and expenses.

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)professionalstock	Mar. 31, 2016USD ($)stock	Dec. 31, 2016USD ($)
Fair Value Measurements (Textual) [Abstract]
AFG's internal investment professionals | professional	25
Number of stocks transferred from Level 1 to Level 2 | stock	0
Number of stocks transferred from Level 2 to Level 1 | stock	0
Level 3 assets as a percentage of total assets measured at fair value	4.00%
Percentage of level 3 assets that were priced using non-binding broker quotes	75.00%
Level 3 assets that were priced using non-binding broker quotes	$ 1,490
Life contingent annuities	$ 203		$ 204
Maximum
Fair Value Measurements (Textual) [Abstract]
Percentage of internally developed Level 3 asset fair values to Shareholders' equity (are less than)	10.00%
Fixed-indexed annuties (embedded derivative), majority of future years | Minimum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	6.00%
Fixed-indexed annuties (embedded derivative), majority of future years | Maximum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	10.00%
Fixed-indexed annuities (embedded derivative)
Fair Value Measurements (Textual) [Abstract]
Fair value of derivatives in annuity benefits accumulated measured using a discounted cash flow approach	$ 1,960
Fixed-indexed annuities (embedded derivative) | Minimum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	3.00%
Fixed-indexed annuities (embedded derivative) | Maximum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	21.00%
Perpetual preferred stocks
Fair Value Measurements (Textual) [Abstract]
Number of stocks transferred from Level 1 to Level 2 | stock		3
Number of stocks transferred from Level 2 to Level 1 | stock		1
Fair value of assets transferred from Level 2 to Level 1, during the first three months		$ 8
Fair value of assets transferred from Level 1 to Level 2, during the first three months		$ 6

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, 2017	Dec. 31, 2016
Assets:
Available for sale (AFS) fixed maturities		$ 36,456	$ 34,544
Trading fixed maturities		359	359
Assets of managed investment entities (“MIE”)		5,331	4,765
Variable annuity assets (separate accounts)	[1]	614	600
Derivatives included in other investments and other assets		573	492
Total assets accounted for at fair value		44,970	42,319
Liabilities:
Liabilities of managed investment entities		5,101	4,549
Total liabilities accounted for at fair value		7,096	6,337
Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		1,963	1,759
Derivatives in long-term debt
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	(1)
Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		32	30
Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		36,456	34,544
Trading fixed maturities		359	359
U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		288	315
States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		6,901	6,781
Foreign government
Assets:
Available for sale (AFS) fixed maturities		138	136
Residential MBS
Assets:
Available for sale (AFS) fixed maturities		3,716	3,635
Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		1,253	1,493
Asset-backed securities (“ABS”)
Assets:
Available for sale (AFS) fixed maturities		6,592	5,959
Corporate and other
Assets:
Available for sale (AFS) fixed maturities		17,568	16,225
Equity securities
Assets:
Equity securities — AFS and trading		1,637	1,558
Other assets — derivatives
Assets:
Derivatives included in other investments and other assets		0	1
Level 1
Assets:
Assets of managed investment entities (“MIE”)		896	380
Variable annuity assets (separate accounts)	[1]	0	0
Total assets accounted for at fair value		2,457	1,877
Liabilities:
Liabilities of managed investment entities		857	363
Total liabilities accounted for at fair value		857	363
Level 1 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 1 | Derivatives in long-term debt
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		152	162
Trading fixed maturities		26	30
Level 1 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		122	133
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 | Asset-backed securities (“ABS”)
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 1 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		30	29
Level 1 | Equity securities
Assets:
Equity securities — AFS and trading		1,383	1,305
Level 1 | Other assets — derivatives
Assets:
Derivatives included in other investments and other assets		0	0
Level 2
Assets:
Assets of managed investment entities (“MIE”)		4,409	4,356
Variable annuity assets (separate accounts)	[1]	614	600
Total assets accounted for at fair value		40,537	38,680
Liabilities:
Liabilities of managed investment entities		4,219	4,158
Total liabilities accounted for at fair value		4,251	4,187
Level 2 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
Level 2 | Derivatives in long-term debt
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	(1)
Level 2 | Other liabilities — derivatives
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		32	30
Level 2 | Fixed maturities
Assets:
Available for sale (AFS) fixed maturities		34,527	32,823
Trading fixed maturities		333	329
Level 2 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		158	174
Level 2 | States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		6,758	6,641
Level 2 | Foreign government
Assets:
Available for sale (AFS) fixed maturities		138	136
Level 2 | Residential MBS
Assets:
Available for sale (AFS) fixed maturities		3,541	3,445
Level 2 | Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		1,224	1,468
Level 2 | Asset-backed securities (“ABS”)
Assets:
Available for sale (AFS) fixed maturities		5,998	5,475
Level 2 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		16,710	15,484
Level 2 | Equity securities
Assets:
Equity securities — AFS and trading		81	79
Level 2 | Other assets — derivatives
Assets:
Derivatives included in other investments and other assets		0	1
Level 3
Assets:
Assets of managed investment entities (“MIE”)		26	29
Variable annuity assets (separate accounts)	[1]	0	0
Total assets accounted for at fair value		1,976	1,762
Liabilities:
Liabilities of managed investment entities		25	28
Total liabilities accounted for at fair value		1,988	1,787
Level 3 | Annuity benefits accumulated
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		1,963	1,759
Level 3 | Derivatives in long-term debt
Liabilities:
Derivatives included in annuity benefits accumulated, long-term debt, and other liabilities		0	0
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		1,777	1,559
Trading fixed maturities		0	0
Level 3 | U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities		8	8
Level 3 | States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities		143	140
Level 3 | Foreign government
Assets:
Available for sale (AFS) fixed maturities		0	0
Level 3 | Residential MBS
Assets:
Available for sale (AFS) fixed maturities		175	190
Level 3 | Commercial MBS
Assets:
Available for sale (AFS) fixed maturities		29	25
Level 3 | Asset-backed securities (“ABS”)
Assets:
Available for sale (AFS) fixed maturities		594	484
Level 3 | Corporate and other
Assets:
Available for sale (AFS) fixed maturities		828	712
Level 3 | Equity securities
Assets:
Equity securities — AFS and trading		173	174
Level 3 | Other assets — derivatives
Assets:
Derivatives included in other investments and other assets		0	0
Equity index call options | Equity index call options
Assets:
Derivatives included in other investments and other assets		573	492
Equity index call options | Level 1 | Equity index call options
Assets:
Derivatives included in other investments and other assets		0	0
Equity index call options | Level 2 | Equity index call options
Assets:
Derivatives included in other investments and other assets		573	492
Equity index call options | Level 3 | Equity index call options
Assets:
Derivatives included in other investments and other assets		$ 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, 2017
Unobservable inputs used by management in determining fair value of embedded derivatives
Risk margin for uncertainty in cash flows	0.68%
Minimum
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary's credit risk	0.20%
Surrenders	3.00%
Partial surrenders	2.00%
Annuitizations	0.10%
Deaths	1.50%
Budgeted option costs	2.40%
Maximum
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary's credit risk	2.80%
Surrenders	21.00%
Partial surrenders	10.00%
Annuitizations	1.00%
Deaths	8.00%
Budgeted option costs	3.60%

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, 2017	Mar. 31, 2016
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	$ 1,762	$ 1,636
Total realized/unrealized gains (losses) included in Net income	(5)	(20)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	14	20
Purchases and issuances	239	102
Sales and settlements	(57)	(23)
Transfer into Level 3	57	72
Transfer out of Level 3	(34)	(16)
Financial assets, Ending Balance	1,976	1,771
Fixed maturities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	1,559	1,470
Total realized/unrealized gains (losses) included in Net income	2	(1)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	7	12
Purchases and issuances	225	90
Sales and settlements	(57)	(23)
Transfer into Level 3	57	57
Transfer out of Level 3	(16)	(16)
Financial assets, Ending Balance	1,777	1,589
U.S. government agency
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	8	15
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	0	0
Transfer into Level 3	0	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	8	15
State and municipal
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	140	89
Total realized/unrealized gains (losses) included in Net income	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	3	3
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	143	92
Residential MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	190	224
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	1	0
Sales and settlements	(8)	(7)
Transfer into Level 3	7	11
Transfer out of Level 3	(16)	(16)
Financial assets, Ending Balance	175	213
Commercial MBS
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	25	39
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	0	(1)
Transfer into Level 3	4	0
Transfer out of Level 3	0	0
Financial assets, Ending Balance	29	38
Asset-backed securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	484	470
Total realized/unrealized gains (losses) included in Net income	0	0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	0	(6)
Purchases and issuances	104	4
Sales and settlements	(11)	(8)
Transfer into Level 3	17	41
Transfer out of Level 3	0	0
Financial assets, Ending Balance	594	501
Corporate and other
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	712	633
Total realized/unrealized gains (losses) included in Net income	1	(2)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	4	15
Purchases and issuances	120	86
Sales and settlements	(38)	(7)
Transfer into Level 3	29	5
Transfer out of Level 3	0	0
Financial assets, Ending Balance	828	730
Equity securities
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	174	140
Total realized/unrealized gains (losses) included in Net income	(6)	(17)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	7	8
Purchases and issuances	12	12
Sales and settlements	0	0
Transfer into Level 3	0	15
Transfer out of Level 3	(14)	0
Financial assets, Ending Balance	173	158
Assets of MIE
Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Financial assets, Beginning Balance	29	26
Total realized/unrealized gains (losses) included in Net income	(1)	(2)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)	0	0
Purchases and issuances	2	0
Sales and settlements	0	0
Transfer into Level 3	0	0
Transfer out of Level 3	(4)	0
Financial assets, Ending Balance	$ 26	$ 24

Fair Value Measurements - Cha44

Fair Value Measurements - Changes in balances of Level 3 financial liabilities carried at fair value (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		$ (1,759)	$ (1,369)
Total realized/unrealized gains (losses) included in Net income		(147)	(17)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0
Purchases and issuances		(79)	(82)
Sales and settlements		22	18
Transfer into Level 3		0	0
Transfer out of Level 3		0	0
Financial liabilities, Ending Balance	[1]	(1,963)	(1,450)
Embedded derivatives
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		(1,759)	(1,369)
Total realized/unrealized gains (losses) included in Net income		(147)	(17)
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0
Purchases and issuances		(79)	(82)
Sales and settlements		22	18
Transfer into Level 3		0	0
Transfer out of Level 3		0	0
Financial liabilities, Ending Balance		$ (1,963)	$ (1,450)
[1]	As discussed previously, 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, 2017	Dec. 31, 2016
Financial assets:
Mortgage loans		$ 1,159	$ 1,147
Policy loans		190	192
Financial liabilities:
Long-term debt		1,283	1,283
Level 1
Financial assets:
Cash and cash equivalents		1,890	2,107
Mortgage loans		0	0
Policy loans		0	0
Total financial assets not accounted for at fair value		1,890	2,107
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		1,379	1,353
Total financial liabilities not accounted for at fair value		1,379	1,353
Level 3
Financial assets:
Cash and cash equivalents		0	0
Mortgage loans		1,158	1,146
Policy loans		190	192
Total financial assets not accounted for at fair value		1,348	1,338
Financial liabilities:
Annuity benefits accumulated	[1]	29,997	28,932
Long-term debt		3	3
Total financial liabilities not accounted for at fair value		30,000	28,935
Carrying Value
Financial assets:
Cash and cash equivalents		1,890	2,107
Mortgage loans		1,159	1,147
Policy loans		190	192
Total financial assets not accounted for at fair value		3,239	3,446
Financial liabilities:
Annuity benefits accumulated	[1]	30,799	29,703
Long-term debt		1,283	1,284
Total financial liabilities not accounted for at fair value		32,082	30,987
Fair Value
Financial assets:
Cash and cash equivalents		1,890	2,107
Mortgage loans		1,158	1,146
Policy loans		190	192
Total financial assets not accounted for at fair value		3,238	3,445
Financial liabilities:
Annuity benefits accumulated	[1]	29,997	28,932
Long-term debt		1,382	1,356
Total financial liabilities not accounted for at fair value		$ 31,379	$ 30,288
[1]	Excludes $203 million and $204 million of life contingent annuities in the payout phase at March 31, 2017 and December 31, 2016, respectively.

Investments - Narrative (Detail

Investments - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)security	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Investment [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	84.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	89.00%
Other than temporary impairment charges	$ 6	$ 52
Average life of ABS	5 years
Average life of MBS	4 years 6 months
Residential MBS
Investment [Line Items]
Non-credit related portion of other-than-temporary impairment charges taken for securities still owned	$ 170		$ 189
Fixed maturities, Gross Unrealized, Losses	(11)		(13)
Securities with non-credit other-than-temporary impairment charges
Investment [Line Items]
Gross Unrealized, Gains	128		130
Gross Unrealized, Losses	(2)		(3)
Fixed maturities
Investment [Line Items]
Fixed maturities, Gross Unrealized, Losses	$ (165)		(245)
Number of available for sale securities in an unrealized loss position | security	1,048
Other than temporary impairment charges	$ 0	$ 16
Common stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position | security	17
Other than temporary impairment charges	$ 3
Equity securities, Gross Unrealized, Losses	$ (21)		(23)
Preferred stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position | security	13
Other than temporary impairment charges	$ 6
Equity securities, Gross Unrealized, Losses	$ (3)		$ (7)
Number of available for sale securities in an unrealized loss position for twelve months or longer | Common stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position | security	0
Number of available for sale securities in an unrealized loss position for twelve months or longer | Preferred stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position | security	1
Maximum | Fixed maturities — all other
Investment [Line Items]
Other than temporary impairment charges	$ 1
Maximum | Residential MBS
Investment [Line Items]
Other than temporary impairment charges	1
Maximum | Corporate bonds
Investment [Line Items]
Other than temporary impairment charges	$ 1

Investments - Available for sal

Investments - Available for sale fixed maturities and equity securities (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	$ 35,445	$ 33,735
Available for sale (AFS) fixed maturities	36,456	34,544
Equity securities, Available for sale, Amortized Cost	1,356	1,351
Equity securities, Available for sale, Fair Value	1,579	1,502
Total fixed maturities
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	35,445	33,735
Fixed maturities, Available for sale, Gross Unrealized, Gains	1,176	1,054
Fixed maturities, Available for sale, Gross Unrealized, Losses	(165)	(245)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	1,011	809
Available for sale (AFS) fixed maturities	36,456	34,544
U.S. Government and government agencies
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	289	315
Fixed maturities, Available for sale, Gross Unrealized, Gains	2	3
Fixed maturities, Available for sale, Gross Unrealized, Losses	(3)	(3)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	(1)	0
Available for sale (AFS) fixed maturities	288	315
States, municipalities and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	6,736	6,650
Fixed maturities, Available for sale, Gross Unrealized, Gains	213	200
Fixed maturities, Available for sale, Gross Unrealized, Losses	(48)	(69)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	165	131
Available for sale (AFS) fixed maturities	6,901	6,781
Foreign government
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	133	131
Fixed maturities, Available for sale, Gross Unrealized, Gains	5	5
Fixed maturities, Available for sale, Gross Unrealized, Losses	0	0
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	5	5
Available for sale (AFS) fixed maturities	138	136
Residential MBS
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	3,432	3,367
Fixed maturities, Available for sale, Gross Unrealized, Gains	295	281
Fixed maturities, Available for sale, Gross Unrealized, Losses	(11)	(13)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	284	268
Available for sale (AFS) fixed maturities	3,716	3,635
Commercial MBS
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	1,211	1,446
Fixed maturities, Available for sale, Gross Unrealized, Gains	43	49
Fixed maturities, Available for sale, Gross Unrealized, Losses	(1)	(2)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	42	47
Available for sale (AFS) fixed maturities	1,253	1,493
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	6,548	5,962
Fixed maturities, Available for sale, Gross Unrealized, Gains	74	43
Fixed maturities, Available for sale, Gross Unrealized, Losses	(30)	(46)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	44	(3)
Available for sale (AFS) fixed maturities	6,592	5,959
Corporate and other
Schedule of Available-for-sale Securities [Line Items]
Fixed maturities, Available for sale, Amortized Cost	17,096	15,864
Fixed maturities, Available for sale, Gross Unrealized, Gains	544	473
Fixed maturities, Available for sale, Gross Unrealized, Losses	(72)	(112)
Fixed maturities, Available for sale, Net Unrealized, Gains (Losses)	472	361
Available for sale (AFS) fixed maturities	17,568	16,225
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Equity securities, Available for sale, Amortized Cost	1,356	1,351
Equity securities, Available for sale, Gross Unrealized, Gains	247	181
Equity securities, Available for sale, Gross Unrealized, Losses	(24)	(30)
Equity securities, Available for sale, Net Unrealized, Gains (Losses)	223	151
Equity securities, Available for sale, Fair Value	1,579	1,502
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Equity securities, Available for sale, Amortized Cost	884	879
Equity securities, Available for sale, Gross Unrealized, Gains	216	160
Equity securities, Available for sale, Gross Unrealized, Losses	(21)	(23)
Equity securities, Available for sale, Net Unrealized, Gains (Losses)	195	137
Equity securities, Available for sale, Fair Value	1,079	1,016
Perpetual preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Equity securities, Available for sale, Amortized Cost	472	472
Equity securities, Available for sale, Gross Unrealized, Gains	31	21
Equity securities, Available for sale, Gross Unrealized, Losses	(3)	(7)
Equity securities, Available for sale, Net Unrealized, Gains (Losses)	28	14
Equity securities, Available for sale, Fair Value	$ 500	$ 486

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, 2017	Dec. 31, 2016
Total fixed maturities
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (123)	$ (196)
Fair Value - Less than twelve months	$ 6,719	$ 8,651
Fair Value as % of Cost - Less than twelve months	98.00%	98.00%
Unrealized Loss - Twelve months or more	$ (42)	$ (49)
Fair Value - Twelve months or more	$ 1,043	$ 1,160
Fair Value as % of Cost - Twelve months or more	96.00%	96.00%
U.S. Government and government agencies
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (1)	$ (1)
Fair Value - Less than twelve months	$ 152	$ 153
Fair Value as % of Cost - Less than twelve months	99.00%	99.00%
Unrealized Loss - Twelve months or more	$ (2)	$ (2)
Fair Value - Twelve months or more	$ 8	$ 8
Fair Value as % of Cost - Twelve months or more	80.00%	80.00%
States, municipalities and political subdivisions
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (44)	$ (64)
Fair Value - Less than twelve months	$ 1,925	$ 2,289
Fair Value as % of Cost - Less than twelve months	98.00%	97.00%
Unrealized Loss - Twelve months or more	$ (4)	$ (5)
Fair Value - Twelve months or more	$ 37	$ 44
Fair Value as % of Cost - Twelve months or more	90.00%	90.00%
Foreign government
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ 0
Fair Value - Less than twelve months	$ 4
Fair Value as % of Cost - Less than twelve months	100.00%
Unrealized Loss - Twelve months or more	$ 0
Fair Value - Twelve months or more	$ 0
Fair Value as % of Cost - Twelve months or more	0.00%
Residential MBS
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (6)	$ (7)
Fair Value - Less than twelve months	$ 455	$ 502
Fair Value as % of Cost - Less than twelve months	99.00%	99.00%
Unrealized Loss - Twelve months or more	$ (5)	$ (6)
Fair Value - Twelve months or more	$ 188	$ 162
Fair Value as % of Cost - Twelve months or more	97.00%	96.00%
Commercial MBS
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (1)	$ (2)
Fair Value - Less than twelve months	$ 71	$ 121
Fair Value as % of Cost - Less than twelve months	99.00%	98.00%
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%
Asset-backed securities
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (14)	$ (29)
Fair Value - Less than twelve months	$ 1,313	$ 1,737
Fair Value as % of Cost - Less than twelve months	99.00%	98.00%
Unrealized Loss - Twelve months or more	$ (16)	$ (17)
Fair Value - Twelve months or more	$ 512	$ 634
Fair Value as % of Cost - Twelve months or more	97.00%	97.00%
Corporate and other
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (57)	$ (93)
Fair Value - Less than twelve months	$ 2,799	$ 3,849
Fair Value as % of Cost - Less than twelve months	98.00%	98.00%
Unrealized Loss - Twelve months or more	$ (15)	$ (19)
Fair Value - Twelve months or more	$ 298	$ 312
Fair Value as % of Cost - Twelve months or more	95.00%	94.00%
Total equity securities
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (23)	$ (29)
Fair Value - Less than twelve months	$ 223	$ 350
Fair Value as % of Cost - Less than twelve months	91.00%	92.00%
Unrealized Loss - Twelve months or more	$ (1)	$ (1)
Fair Value - Twelve months or more	$ 6	$ 6
Fair Value as % of Cost - Twelve months or more	86.00%	86.00%
Common stocks
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (21)	$ (23)
Fair Value - Less than twelve months	$ 138	$ 215
Fair Value as % of Cost - Less than twelve months	87.00%	90.00%
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%
Perpetual preferred stocks
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ (2)	$ (6)
Fair Value - Less than twelve months	$ 85	$ 135
Fair Value as % of Cost - Less than twelve months	98.00%	96.00%
Unrealized Loss - Twelve months or more	$ (1)	$ (1)
Fair Value - Twelve months or more	$ 6	$ 6
Fair Value as % of Cost - Twelve months or more	86.00%	86.00%

Investments - Credit portion of

Investments - Credit portion of other-than-temporary impairments on fixed maturities for which the non-credit portion of an impairment has been recognized in OCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning Balance	$ 153	$ 160
Additional credit impairments on:
Previously impaired securities	0	2
Securities without prior impairments	0	0
Reductions due to sales or redemptions	(7)	(2)
Ending Balance	$ 146	$ 160

Investments - Scheduled maturit

Investments - Scheduled maturities of available for sale fixed maturities (Details) - Fixed maturities $ in Millions	Mar. 31, 2017USD ($)
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
One year or less	$ 1,038
After one year through five years	6,034
After five years through ten years	12,717
After ten years	4,465
Fixed maturities amortized cost, Subtotal	24,254
ABS (average life of approximately 5 years)	6,548
MBS (average life of approximately 4-1/2 years)	4,643
Amortized Cost	35,445
Fair Value, Fiscal Year Maturity [Abstract]
One year or less	1,051
After one year through five years	6,300
After five years through ten years	12,990
After ten years	4,554
Fixed maturities fair value, Subtotal	24,895
ABS (average life of approximately 5 years)	6,592
MBS (average life of approximately 4-1/2 years)	4,969
Fair Value	$ 36,456
Fair Value Percent, Fiscal Year Maturity [Abstract]
One year or less	3.00%
After one year through five years	17.00%
After five years through ten years	36.00%
After ten years	12.00%
Fixed maturities fair value, Subtotal, Percent	68.00%
ABS (average life of approximately 5 years)	18.00%
MBS (average life of approximately 4-1/2 years)	14.00%
Fair value, Total, Percent	100.00%

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, 2017	Dec. 31, 2016
Unrealized gain on:
Pretax		$ 813	$ 622
Deferred Tax		(284)	(218)
Net		529	404
Total investments
Unrealized gain on:
Pretax		1,234	960
Deferred Tax		(432)	(336)
Net		802	624
Total fixed maturities
Unrealized gain on:
Pretax		1,011	809
Deferred Tax		(354)	(283)
Net		657	526
Fixed maturities — annuity segment
Unrealized gain on:
Pretax	[1]	800	640
Deferred Tax	[1]	(280)	(224)
Net	[1]	520	416
Fixed maturities — all other
Unrealized gain on:
Pretax		211	169
Deferred Tax		(74)	(59)
Net		137	110
Equity securities
Unrealized gain on:
Pretax		223	151
Deferred Tax		(78)	(53)
Net		145	98
Deferred policy acquisition costs — annuity segment
Unrealized gain on:
Pretax		(333)	(273)
Deferred Tax		117	96
Net		(216)	(177)
Annuity benefits accumulated
Unrealized gain on:
Pretax		(103)	(78)
Deferred Tax		36	27
Net		(67)	(51)
Unearned revenue
Unrealized gain on:
Pretax		15	13
Deferred Tax		(5)	(5)
Net		$ 10	$ 8
[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, 2017	Mar. 31, 2016
Net Investment Income [Line Items]
Investment income	$ 440	$ 416
Investment expenses	(5)	(5)
Net investment income	435	411
Fixed maturities
Net Investment Income [Line Items]
Investment income	389	367
Equity securities
Net Investment Income [Line Items]
Investment income	21	19
Equity in earnings of partnerships and similar investments
Net Investment Income [Line Items]
Investment income	10	11
Other
Net Investment Income [Line Items]
Investment income	$ 20	$ 19

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, 2017	Mar. 31, 2016
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	$ 9	$ 34
Realized — impairments	(6)	(52)
Realized gains (losses) on securities	3	(18)
Net of tax and noncontrolling interests
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	6	22
Realized — impairments	(4)	(32)
Realized gains (losses) on securities	2	(10)
Change in unrealized	125	134
Total pretax
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	9	34
Realized — impairments	(6)	(52)
Realized gains (losses) on securities	3	(18)
Change in unrealized	191	210
Fixed maturities
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	5	14
Realized — impairments	0	(16)
Realized gains (losses) on securities	5	(2)
Change in unrealized	202	453
Equity securities
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	2	23
Realized — impairments	(9)	(41)
Realized gains (losses) on securities	(7)	(18)
Change in unrealized	72	(23)
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	3	0
Realized — impairments	0	0
Realized gains (losses) on securities	3	0
Change in unrealized	0	0
Other, Including DPAC and reserves on annuities and long-term care
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	(1)	(3)
Realized — impairments	3	5
Realized gains (losses) on securities	2	2
Change in unrealized	(83)	(220)
Tax effects
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	(3)	(12)
Realized — impairments	2	19
Realized gains (losses) on securities	(1)	7
Change in unrealized	(66)	(74)
Noncontrolling interests
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments
Realized before impairments	0	0
Realized — impairments	0	1
Realized gains (losses) on securities	0	1
Change in unrealized	$ 0	$ (2)

Investments - Gross realized ga

Investments - Gross realized gains and losses on available for sale fixed maturity and equity security investment transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Fixed maturities
Gross realized gains and losses on the sale of available for sale fixed maturity and equity security investments
Gross gains	$ 5	$ 14
Gross losses	0	(1)
Equity securities
Gross realized gains and losses on the sale of available for sale fixed maturity and equity security investments
Gross gains	4	25
Gross losses	$ (2)	$ 0

Derivatives - Narrative (Detail

Derivatives - Narrative (Details)	3 Months Ended
	Mar. 31, 2017USD ($)swap	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Carrying value of collateral received to support purchased call options	$ 387,000,000		$ 380,000,000
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	7
Notional amount of derivative instrument outstanding	$ 1,030,000,000		1,080,000,000
Gain (loss) reclassified from AOCI into net investment income	2,000,000	$ 2,000,000
Gain (loss) on cash flow hedge ineffectiveness recorded in Net Earnings	0	0
Collateral receivable supporting interest rate swaps	60,000,000		60,000,000
Other assets | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value			1,000,000
Other assets | Maximum | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value	1,000,000
Other liabilities | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value	$ (24,000,000)		$ (22,000,000)
Senior Notes | 9-7/8% Senior Notes due June 2019
Derivative Instruments, Gain (Loss) [Line Items]
Stated interest rate, percentage	9.875%
AFG
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate description of fair value hedge activity	three-month LIBOR plus 8.099%
AFG | Fair Value Hedge | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Effective interest rate, percentage	9.2302%		9.0624%
The net reduction in interest expense from interest rate swaps	$ 1,000,000	$ 1,000,000
AFG | Long-term debt | Fair Value Hedge | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value			$ 1,000,000
AFG | Long-term debt | Maximum | Fair Value Hedge | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net derivatives, at fair value	$ 1,000,000
AFG | Senior Notes | 9-7/8% Senior Notes due June 2019
Derivative Instruments, Gain (Loss) [Line Items]
Stated interest rate, percentage	9.875%		9.875%
AFG | LIBOR | Fair Value Hedge | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Basis spread on variable interest rate	8.099%

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, 2017	Dec. 31, 2016
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	$ 681	$ 603
Derivative liability, at fair value	1,971	1,767
MBS with embedded derivatives | Fixed maturities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	104	107
Public company warrants | Equity securities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	4	4
Fixed-indexed annuities (embedded derivative) | Annuity benefits accumulated
Derivatives included in AFG' s Balance Sheet at fair value
Derivative liability, at fair value	1,963	1,759
Equity index call options | Equity index call options
Derivatives included in AFG' s Balance Sheet at fair value
Derivative asset, at fair value	573	492
Reinsurance contracts (embedded derivative) | Other liabilities
Derivatives included in AFG' s Balance Sheet at fair value
Derivative liability, at fair value	$ 8	$ 8

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, 2017	Mar. 31, 2016
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ (7)	$ (61)
MBS with embedded derivatives | Realized gains on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	0	1
Public company warrants | Realized gains on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	0	(2)
Fixed-indexed annuities (embedded derivative) | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	(147)	(17)
Equity index call options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	141	(40)
Reinsurance contracts (embedded derivative) | Net investment income
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ (1)	$ (3)

Deferred Policy Acquisition C58

Deferred Policy Acquisition Costs - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Deferred Policy Acquisition Costs Disclosures [Abstract]
Accumulated amortization of present value of future profits	$ 136	$ 134

Deferred Policy Acquisition C59

Deferred Policy Acquisition Costs - Progression of deferred policy acquisition costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
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	$ 1,239	$ 1,184
Deferred policy acquisition costs and present value of future profits, additions	207	205
Deferred policy acquisition costs and present value of future profits, periodic amortization	(185)	(166)
Deferred policy acquisition costs and present value of future profits, change included in realized gains	2	2
Deferred policy acquisition costs and present value of future profits, foreign currency translation	1
Deferred policy acquisition costs and present value of future profits, change in unrealized	(59)	(170)
Deferred policy acquisition costs and present value of future profits, ending balance	1,205	1,055
P&C
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs, beginning balance	238	226
Deferred policy acquisition costs, additions	139	132
Deferred policy acquisition costs, periodic amortization	(135)	(134)
Deferred policy acquisition costs, foreign currency translation	1
Deferred policy acquisition costs, ending balance	243	224
Annuity and Run-off Long-term Care and Life
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs, beginning balance	1,110	1,018
Deferred policy acquisition costs, additions	67	68
Deferred policy acquisition costs, periodic amortization	(42)	(25)
Deferred policy acquisition costs, change included in realized gains	2	2
Deferred policy acquisition costs, ending balance	1,137	1,063
Movement in Deferred Sales Inducements [Roll Forward]
Deferred sales inducements, beginning balance	110	119
Deferred sales inducements, additions	1	5
Deferred sales inducements, periodic amortization	(6)	(5)
Deferred sales inducements, change included in realized gains	0	0
Deferred sales inducements, ending balance	105	119
Movement in Present Value of Future Insurance Profits [Roll Forward]
Present value of future profits, beginning balance	46	55
Present value of future profits, periodic amortization	(2)	(2)
Present value of future profits, ending balance	44	53
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	(265)	(234)
Unrealized investment gains (losses), change in unrealized	(59)	(170)
Unrealized investment gains (losses), ending balance	(324)	(404)
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	1,001	958
Deferred policy acquisition costs and present value of future profits, additions	68	73
Deferred policy acquisition costs and present value of future profits, periodic amortization	(50)	(32)
Deferred policy acquisition costs and present value of future profits, change included in realized gains	2	2
Deferred policy acquisition costs and present value of future profits, change in unrealized	(59)	(170)
Deferred policy acquisition costs and present value of future profits, ending balance	962	831
Excluding Unrealized Gains | Annuity and Run-off Long-term Care and Life
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	1,266	1,192
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	$ 1,286	$ 1,235

Managed Investment Entities - N

Managed Investment Entities - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended
	Mar. 31, 2017USD ($)	Mar. 31, 2017USD ($)collateralizedloanobligation	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
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		64.40%
Number of collateralized loan obligation entities | collateralizedloanobligation		16
Face amount of managed investment entities liabilities purchased by subsidiaries after issuance date			$ 11
Amount paid by subsidiaries to purchase managed investment entities liabilities after issuance date			10
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities		$ 4	23
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	$ 59	59		$ 75
Difference between aggregate unpaid principal balance and carrying value of CLOs' debt	140	140		159
Carrying amount of CLO loans in default	1	1		1
Aggregate unpaid principal balance of CLO loans in default	8	8		10
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	230	230	$ 250	$ 216
New Collateralized Loan Obligation Entities
Variable Interest Entity [Line Items]
Face value of liabilities issued by managed investment entities on issuance date	408
Face amount of managed investment entities liabilities purchased by subsidiaries at issuance date	24
Subordinated Debt Obligations | Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	$ 160	$ 160

Managed Investment Entities - S

Managed Investment Entities - Selected financial information related to CLOs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Gains (losses) on change in fair value of assets/liabilities:
Assets	[1]	$ 5	$ (1)
Liabilities	[1]	(5)	(12)
Management fees paid to AFG		4	4
CLO earnings (losses) attributable to AFG shareholders	[2]	6	(7)
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Investment in CLO tranches at end of period		$ 230	$ 250	$ 216
[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, 2017	Mar. 31, 2016	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the goodwill balance during the period	$ 0
Goodwill	199,000,000		$ 199,000,000
Amortizable intangible assets related to property and casualty insurance acquisitions	32,000,000		34,000,000
Accumulated amortization	24,000,000		$ 25,000,000
Amortization of intangible assets	$ 2,000,000	$ 2,000,000

Long-Term Debt - Schedule of lo

Long-Term Debt - Schedule of long-term debt (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Summary of Carrying value of long-term debt
Principal	$ 1,308	$ 1,308
Discount and Issue Costs	(25)	(25)
Carrying Value	1,283	1,283
Senior Notes | AFG
Summary of Carrying value of long-term debt
Principal	1,008	1,008
Discount and Issue Costs	(15)	(15)
Carrying Value	993	993
Senior Notes | 9-7/8% Senior Notes due June 2019 | AFG
Summary of Carrying value of long-term debt
Principal	350	350
Discount and Issue Costs	(1)	(1)
Carrying Value	349	349
Senior Notes | 3.50% Senior Notes due August 2026 | AFG
Summary of Carrying value of long-term debt
Principal	300	300
Discount and Issue Costs	(3)	(3)
Carrying Value	297	297
Senior Notes | 6-3/8% Senior Notes due June 2042 | AFG
Summary of Carrying value of long-term debt
Principal	230	230
Discount and Issue Costs	(7)	(7)
Carrying Value	223	223
Senior Notes | 5-3/4% Senior Notes due August 2042 | AFG
Summary of Carrying value of long-term debt
Principal	125	125
Discount and Issue Costs	(4)	(4)
Carrying Value	121	121
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	300	300
Discount and Issue Costs	(10)	(10)
Carrying Value	290	290
Subordinated Debentures | 6-1/4% Subordinated Debentures due September 2054 | AFG
Summary of Carrying value of long-term debt
Principal	150	150
Discount and Issue Costs	(5)	(5)
Carrying Value	145	145
Subordinated Debentures | 6% Subordinated Debentures due November 2055 | AFG
Summary of Carrying value of long-term debt
Principal	150	150
Discount and Issue Costs	(5)	(5)
Carrying Value	$ 145	$ 145

Long-Term Debt - Narrative (Det

Long-Term Debt - Narrative (Details) - USD ($)	Mar. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Long-term Debt, Fiscal Year Maturity [Abstract]
Scheduled principal payments on debt in 2017	$ 0	$ 0
Scheduled principal payments on debt in 2018	0	0
Scheduled principal payments on debt in 2019	350,000,000	350,000,000
Scheduled principal payments on debt in 2020	0	0
Scheduled principal payments on debt in 2021	0	0
Scheduled principal payments on debt in 2022	0	0
Scheduled principal payments on debt after 2022	958,000,000	958,000,000
AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Revolving credit line	500,000,000	500,000,000
Amount borrowed under revolving credit facility	$ 0	$ 0	$ 0
Interest rate description of fair value hedge activity		three-month LIBOR plus 8.099%
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%
Interest rate swaps | Fair Value Hedge | Designated as Hedging Instrument | AFG
Debt Instrument [Line Items]
Effective interest rate, percentage	9.2302%	9.2302%	9.0624%
Interest rate swaps | Fair Value Hedge | Designated as Hedging Instrument | LIBOR | AFG
Debt Instrument [Line Items]
Basis spread on variable interest rate	8.099%	8.099%
Long-term debt | Interest rate swaps | Fair Value Hedge | Designated as Hedging Instrument | AFG
Debt Instrument [Line Items]
Net derivatives, at fair value			$ 1,000,000
Long-term debt | Interest rate swaps | Fair Value Hedge | Designated as Hedging Instrument | AFG | Maximum
Debt Instrument [Line Items]
Net derivatives, at fair value	$ 1,000,000	$ 1,000,000
Senior Notes | 9-7/8% Senior Notes due June 2019
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	9.875%	9.875%
Senior Notes | 9-7/8% Senior Notes due June 2019 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	9.875%	9.875%	9.875%
Senior Notes | 3.50% Senior Notes due August 2026 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	3.50%	3.50%
Senior Notes | 6-3/8% Senior Notes due June 2042 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	6.375%	6.375%
Senior Notes | 5-3/4% Senior Notes due August 2042 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	5.75%	5.75%
Subordinated Debt | 6-1/4% Subordinated Debentures due September 2054 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	6.25%	6.25%
Subordinated Debt | 6% Subordinated Debentures due November 2055 | AFG
Long-term Debt, Fiscal Year Maturity [Abstract]
Stated interest rate, percentage	6.00%	6.00%

Shareholders' Equity - Preferre

Shareholders' Equity - Preferred stock authorized for issuance (Details)	Mar. 31, 2017$ / sharesshares
Voting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, par value | $ / shares	$ 0
Preferred Stock, shares authorized | shares	12,500,000
Nonvoting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, par value | $ / shares	$ 0
Preferred Stock, shares authorized | shares	12,500,000

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net of tax unrealized gains (losses) related to credit-only impaired securities	$ 52		$ 52
Compensation expense related to stock incentive plans	$ 11	$ 8
Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Common Stock, shares issued (shares)	232,250
Restricted Common Stock, fair value per share (USD per share)	$ 94.44
Common Stock options issued under stock incentive plan (shares)	0
Annual Equity Bonus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other benefit plans, shares issued (shares)		47,826
Common Stock issued, fair value per share (USD per share)		$ 96.13

Shareholders' Equity - Progress

Shareholders' Equity - Progression of the components of accumulated other comprehensive income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017		Mar. 31, 2016
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		$ 375
Other comprehensive income, net of tax		124		$ 146
AOCI ending balance		499
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		191		192
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, tax		(66)		(67)
Other comprehensive income (loss), unrealized holding gains on securities arising during the period, net of tax		125		125
Reclassification from accumulated other comprehensive income, pretax	[1]	0		18
Reclassification from accumulated other comprehensive income, tax	[1]	0		(7)
Reclassification from accumulated other comprehensive income, net of tax		0		11
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		191		210
Other comprehensive income (loss), tax		(66)		(74)
Other comprehensive income, net of tax		125		136
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		(1)
Reclassification from accumulated other comprehensive income, net of tax	[1]	0		(1)
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income, net of tax		0		(2)
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		125		124
Reclassification from accumulated other comprehensive income, net of tax		0		10
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		404	[2]	332
Other comprehensive income, net of tax		125		134
AOCI ending balance		529	[2]	466
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		(2)		5
Other comprehensive income (loss), tax		1		(2)
Other comprehensive income, net of tax		(1)		3
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income, 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		(7)		1
Other comprehensive income, net of tax		(1)		3
AOCI ending balance		(8)		4
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		0		3
Other comprehensive income (loss), tax		0		3
Other comprehensive income, net of tax		0		6
Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income, net of tax		0		0
Accumulated Foreign Currency Adjustment Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		(15)		(22)
Other comprehensive income, net of tax		0		6
AOCI ending balance		(15)		(16)
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		0		1
Other comprehensive income (loss), tax		0		0
Other comprehensive income, net of tax		0		1
Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income, net of tax		0		0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		(7)		(7)
Other comprehensive income, net of tax		0		1
AOCI ending balance		(7)		(6)
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), pretax		189		219
Other comprehensive income (loss), tax		(65)		(73)
Other comprehensive income, net of tax		124		146
AOCI Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income, net of tax		0		(2)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance		375		304
Other comprehensive income, net of tax		124		144
AOCI ending balance		$ 499		$ 448
[1]	The reclassification adjustment out of net unrealized gains 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 for income taxes Attributable to noncontrolling interests Net earnings (loss) attributable to noncontrolling interests
[2]	Includes net unrealized gains of $52 million at both March 31, 2017 and December 31, 2016 related to securities for which only the credit portion of an other-than-temporary impairment has been recorded in earnings.

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Statutory rate of income taxes	35.00%	35.00%

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, 2017	Mar. 31, 2016
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Earnings before income taxes (“EBT”)	$ 223	$ 156
Income taxes at statutory rate	78	55
Effect of tax exempt interest	(6)	(7)
Effect of stock-based compensation	(6)	0
Effect of change in valuation allowance	(2)	1
Effect of subsidiaries not in AFG's tax return	0	1
Effect of other income tax reconciliation	4	2
Provision for income taxes as shown on the Statement of Earnings	$ 68	$ 52
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income taxes at statutory rate as a percentage of EBT	35.00%	35.00%
Effect of tax exempt interest as a percentage of EBT	(3.00%)	(4.00%)
Effect of stock-based compensation as a percentage of EBT	(3.00%)	0.00%
Effect of change in valuation allowance as a percentage of EBT	(1.00%)	1.00%
Effect of subsidiaries not in AFG's tax return as a percentage of EBT	0.00%	0.00%
Effect of other income tax reconciliation as a percentage of EBT	2.00%	1.00%
Provision for income taxes as shown on the Statement of Earnings as a percentage of EBT	30.00%	33.00%

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, 2017	Mar. 31, 2016
Analysis of changes in the liability for losses and loss adjustment expenses, net of reinsurance
Balance at beginning of year	$ 8,563	$ 8,127
Less reinsurance recoverables, net of allowance	2,302	2,201
Net liability at beginning of year	6,261	5,926
Liability for losses and loss adjustment expenses, period increase (decrease) [Abstract]
Provision for losses and LAE occurring in the current period	637	609
Net increase (decrease) in the provision for claims of prior years:
Net increase (decrease) in the provision for claims of prior years	(28)	(28)
Total losses and LAE incurred	609	581
Payments for losses and LAE of:
Current year	(84)	(80)
Prior years	(470)	(467)
Total payments	(554)	(547)
Foreign currency translation and other	8	11
Net liability at end of period	6,324	5,971
Add back reinsurance recoverables, net of allowance	2,297	2,137
Gross unpaid losses and LAE included in the balance sheet at end of period	$ 8,621	$ 8,108

Subsequent Event - Narrative (D

Subsequent Event - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	May 03, 2017	Mar. 31, 2017	Mar. 31, 2016
Subsequent Event [Line Items]
Special cash dividend payable (USD per share)		$ 0.3125	$ 0.28
Aggregate amount of special cash dividend		$ (27)	$ (24)
Subsequent Event
Subsequent Event [Line Items]
Special cash dividend payable (USD per share)	$ 1.50
Aggregate amount of special cash dividend	$ (132)