v2.4.0.6

Reconciliation of Statutory Federal Income Tax Rate to Effective Tax Rate (Parenthetical) (Detail) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011
Income Taxes [Line Items] |  |  |  |
Federal statutory rate | 35.00% | 35.00% | 35.00% | 35.00%

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- Details
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Namespace Prefix: | afsi_
Data Type: | xbrli:stringItemType
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Period Type: | duration

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- Definition US Federal Statutory Income Tax Rate + References No definition available. + Details
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Namespace Prefix: | afsi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration