v2.3.0.15
Segment Reporting Disclosures (Company's Segment Disclosures) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended9 Months Ended
Sep. 30, 2011
Sep. 30, 2010
Sep. 30, 2011
Sep. 30, 2010
Segment Reporting Information [Line Items]    
Gross premium volume$ 584,635$ 521,591$ 1,772,611$ 1,528,129
Net written premiums524,678467,1551,574,3781,367,886
Earned premiums509,203435,3551,462,5151,264,178
Losses and loss adjustment expenses, Current accident year(405,575)(330,290)(1,177,848)(916,761)
Losses and loss adjustment expenses, Prior accident years98,943105,450250,205180,516
Underwriting, acquisition and insurance expenses(202,316)(181,640)(601,511)(517,414)
Underwriting profit (loss)25528,875(66,639)10,519
Net investment income62,19968,652196,551201,438
Net realized investment gains (losses)12,8398,78225,42322,096
Other revenues (insurance)10,0611,26731,6226,182
Other expenses (insurance)(2,999)(618)(27,374)(5,482)
Segment profit (loss)82,355106,958159,583234,753
Other revenues (non-insurance)81,78647,298228,739119,593
Other expenses (non-insurance)(67,303)(40,456)(190,896)(103,958)
Amortization of intangible assets(6,023)(3,903)(17,586)(11,717)
Interest expense(23,656)(18,598)(64,516)(54,891)
Income before income taxes67,15991,299115,324183,780
U.S. GAAP combined ratio100.00%[1]93.00%[1]105.00%[1]99.00%[1]
Excess And Surplus Lines [Member]
    
Segment Reporting Information [Line Items]    
Gross premium volume236,639238,622663,989692,949
Net written premiums200,658208,299570,243618,835
Earned premiums189,695207,166557,958621,331
Losses and loss adjustment expenses, Current accident year(147,992)(175,289)(413,049)(452,774)
Losses and loss adjustment expenses, Prior accident years60,47552,751169,916103,453
Underwriting, acquisition and insurance expenses(81,563)(89,986)(250,415)(260,526)
Underwriting profit (loss)20,615(5,358)64,41011,484
Net investment income0000
Net realized investment gains (losses)0000
Other revenues (insurance)0000
Other expenses (insurance)0000
Segment profit (loss)20,615(5,358)64,41011,484
Amortization of intangible assets    
Interest expense    
Income before income taxes    
U.S. GAAP combined ratio89.00%[1]103.00%[1]88.00%[1]98.00%[1]
Specialty Admitted [Member]
    
Segment Reporting Information [Line Items]    
Gross premium volume153,753104,292431,604261,138
Net written premiums147,16998,521410,700242,199
Earned premiums136,78379,396390,623227,000
Losses and loss adjustment expenses, Current accident year(112,607)(51,299)(285,401)(143,097)
Losses and loss adjustment expenses, Prior accident years5,9733,8917,9424,803
Underwriting, acquisition and insurance expenses(51,695)(31,931)(148,957)(90,088)
Underwriting profit (loss)(21,546)57(35,793)(1,382)
Net investment income0000
Net realized investment gains (losses)0000
Other revenues (insurance)10,061031,6220
Other expenses (insurance)(3,046)0(27,374)0
Segment profit (loss)(14,531)57(31,545)(1,382)
Amortization of intangible assets    
Interest expense    
Income before income taxes    
U.S. GAAP combined ratio116.00%[1]100.00%[1]109.00%[1]101.00%[1]
London Insurance Market [Member]
    
Segment Reporting Information [Line Items]    
Gross premium volume194,210178,677676,893573,999
Net written premiums176,829160,120593,440506,594
Earned premiums182,710148,579513,947415,590
Losses and loss adjustment expenses, Current accident year(144,976)(103,702)(479,398)(320,890)
Losses and loss adjustment expenses, Prior accident years34,72149,27769,96075,160
Underwriting, acquisition and insurance expenses(69,731)(59,585)(202,291)(166,674)
Underwriting profit (loss)2,72434,569(97,782)3,186
Net investment income0000
Net realized investment gains (losses)0000
Other revenues (insurance)01,26706,182
Other expenses (insurance)47(618)0(5,482)
Segment profit (loss)2,77135,218(97,782)3,886
Amortization of intangible assets    
Interest expense    
Income before income taxes    
U.S. GAAP combined ratio99.00%[1]77.00%[1]119.00%[1]99.00%[1]
Other Insurance (Discontinued Lines) [Member]
    
Segment Reporting Information [Line Items]    
Gross premium volume33012543
Net written premiums22215(5)258
Earned premiums15214(13)257
Losses and loss adjustment expenses, Current accident year0000
Losses and loss adjustment expenses, Prior accident years(2,226)(469)2,387(2,900)
Underwriting, acquisition and insurance expenses673(138)152(126)
Underwriting profit (loss)(1,538)(393)2,526(2,769)
Net investment income0000
Net realized investment gains (losses)0000
Other revenues (insurance)0000
Other expenses (insurance)0000
Segment profit (loss)(1,538)(393)2,526(2,769)
Amortization of intangible assets    
Interest expense    
Income before income taxes    
U.S. GAAP combined ratio [1],[2] [1],[2] [1],[2] [1],[2]
Investing [Member]
    
Segment Reporting Information [Line Items]    
Gross premium volume0000
Net written premiums0000
Earned premiums0000
Losses and loss adjustment expenses, Current accident year0000
Losses and loss adjustment expenses, Prior accident years0000
Underwriting, acquisition and insurance expenses0000
Underwriting profit (loss)0000
Net investment income62,19968,652196,551201,438
Net realized investment gains (losses)12,8398,78225,42322,096
Other revenues (insurance)0000
Other expenses (insurance)0000
Segment profit (loss)75,03877,434221,974223,534
Amortization of intangible assets    
Interest expense    
Income before income taxes    
U.S. GAAP combined ratio   [1] 
[1] The U.S. GAAP combined ratio is a measure of underwriting performance and represents the relationship of incurred losses, loss adjustment expenses and underwriting, acquisition and insurance expenses to earned premiums.
[2] NM - Ratio is not meaningful.