v2.4.0.6

Ownership Components of Total Equity (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011
Stockholders Equity [Line Items] |  |  |  |
Beginning Balance, January 1, 2012 |  |  | $ 959,661 |
Net income | 45,893 | 40,182 | 125,753 | 153,422
Unrealized holding gains and reclassification |  |  | 56,265 |
Foreign currency translation |  |  | 4,624 |
Unrealized loss on interest rate swap |  |  | (952) |
Equity component of convertible senior notes, net of income tax and issue costs |  |  | 3,306 |
Capital contribution |  |  | 16,624 |
Acquisition of non-controlling interest |  |  | 0 |
Dividends |  |  | (18,200) |
Share exercises and compensation, other |  |  | 9,130 |
Ending Balance, Sept 30, 2012 | 1,156,211 |  | 1,156,211 |
AmTrust |  |  |  |
Stockholders Equity [Line Items] |  |  |  |
Beginning Balance, January 1, 2012 |  |  | 890,563 |
Net income |  |  | 122,674 |
Unrealized holding gains and reclassification |  |  | 56,265 |
Foreign currency translation |  |  | 4,624 |
Unrealized loss on interest rate swap |  |  | (952) |
Equity component of convertible senior notes, net of income tax and issue costs |  |  | 3,306 |
Acquisition of non-controlling interest |  |  | 6,900 |
Dividends |  |  | (18,200) |
Share exercises and compensation, other |  |  | 9,130 |
Ending Balance, Sept 30, 2012 | 1,074,310 |  | 1,074,310 |
Non-Controlling Interests |  |  |  |
Stockholders Equity [Line Items] |  |  |  |
Beginning Balance, January 1, 2012 |  |  | 69,098 |
Net income |  |  | 3,079 |
Capital contribution |  |  | 16,624 |
Acquisition of non-controlling interest |  |  | (6,900) |
Ending Balance, Sept 30, 2012 | $ 81,901 |  | $ 81,901 |

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- Definition Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 25 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=6928081&loc=SL6014347-161799 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 65 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7667209&loc=SL6052262-162007 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number APB14-1 -Paragraph 12 -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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