v2.4.0.6

Trust Preferred Securities (Detail) (USD $) In Thousands, unless otherwise specified | 9 Months Ended |
--- | --- | ---
Sep. 30, 2012 | Dec. 31, 2011
Debt Instrument [Line Items] |  |  |
Aggregate Liquidation Amount of Trust Preferred Securities | $ 120,000 |  |
Aggregate Liquidation Amount of Common Securities | 3,714 |  |
Aggregate Principal Amount of Notes | 123,714 |  | 123,714
Stated Maturity of Notes | Dec. 15, 2021 |  |
Per Annum Interest Rate of Notes | 5.50% |  |
AmTrust Capital Financing Trust I |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate Liquidation Amount of Trust Preferred Securities | 25,000 |  |
Aggregate Liquidation Amount of Common Securities | 774 |  |
Aggregate Principal Amount of Notes | 25,774 |  |
Stated Maturity of Notes | Mar. 17, 2035 |  |
Per Annum Interest Rate of Notes | 8.275% | [1] |
AmTrust Capital Financing Trust II |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate Liquidation Amount of Trust Preferred Securities | 25,000 |  |
Aggregate Liquidation Amount of Common Securities | 774 |  |
Aggregate Principal Amount of Notes | 25,774 |  |
Stated Maturity of Notes | Jun. 15, 2035 |  |
Per Annum Interest Rate of Notes | 7.71% | [1] |
AmTrust Capital Financing Trust III |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate Liquidation Amount of Trust Preferred Securities | 30,000 |  |
Aggregate Liquidation Amount of Common Securities | 928 |  |
Aggregate Principal Amount of Notes | 30,928 |  |
Stated Maturity of Notes | Sep. 15, 2036 |  |
Per Annum Interest Rate of Notes | 3.689% | [2] |
AmTrust Capital Financing Trust IV |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate Liquidation Amount of Trust Preferred Securities | 40,000 |  |
Aggregate Liquidation Amount of Common Securities | 1,238 |  |
Aggregate Principal Amount of Notes | $ 41,238 |  |
Stated Maturity of Notes | Mar. 15, 2037 |  |
Per Annum Interest Rate of Notes | 3.389% | [3] |
[1] | The interest rate will change to three-month LIBOR plus 3.40% after the tenth anniversary in 2015.
[2] | The interest rate is LIBOR plus 3.30%.
[3] | The interest rate is LIBOR plus 3.00%.

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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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