XML 43 R32.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Accounting Policies (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2013
Variable Interest Entity [Line Items] |  |  |  |  |
Assets | $ 2,946 |  | $ 2,946 |  | $ 2,888
Liabilities | 2,625 |  | 2,625 |  | 2,567
Weighted average common shares adjustment related to stock-based compensation | 1.9 | 1.9 | 2.0 | 1.8 |
Anti-dilutive potential common shares related to stock-based compensation plans | 1.2 | 1.0 | 1.0 | 1.3 |
Maturities of short term investments |  |  | 3 months |  |
New collateralized loan obligation temporary warehousing entities [Member] |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Assets | 153 |  | 153 |  |
Liabilities | $ 124 |  | $ 124 |  |

X
- Definition Maturity period of short term investment maximum. + References No definition available. + Details
Name: | afg_MaturityPeriodOfShortTermInvestmentMaximum
Namespace Prefix: | afg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Diluted Earnings Per Share -URI http://asc.fasb.org/extlink&oid=6510752 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 + Details
Name: | us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 28A -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1500-109256 + Details
Name: | us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685 + Details
Name: | us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685 + Details
Name: | us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_VariableInterestEntityLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration