v2.4.0.6
Derivative Instruments (Gain (Loss) Recognized In The Consolidated Statements Of Operations Related To Its Derivative Instruments) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 3 Months Ended 6 Months Ended 0 Months Ended 6 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Net Investment Income [Member]
Interest Rate Futures [Member]
Jun. 30, 2011
Net Investment Income [Member]
Interest Rate Futures [Member]
Jun. 30, 2012
Net Investment Income [Member]
Interest Rate Futures [Member]
Jun. 30, 2011
Net Investment Income [Member]
Interest Rate Futures [Member]
Jun. 30, 2012
Net Investment Income [Member]
Credit Default Swap [Member]
Jun. 30, 2011
Net Investment Income [Member]
Credit Default Swap [Member]
Jun. 30, 2012
Net Investment Income [Member]
Credit Default Swap [Member]
Jun. 30, 2011
Net Investment Income [Member]
Credit Default Swap [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Investment Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Investment Operations [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Investment Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Investment Operations [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Energy And Risk Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Energy And Risk Operations [Member]
Jun. 30, 2012
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Energy And Risk Operations [Member]
Jun. 30, 2011
Net Foreign Exchange Gains (Losses) [Member]
Foreign Currency Forward Contracts, Energy And Risk Operations [Member]
Jun. 30, 2012
Other Income (Loss) [Member]
Energy And Weather Contracts [Member]
Jun. 30, 2011
Other Income (Loss) [Member]
Energy And Weather Contracts [Member]
Jun. 30, 2012
Other Income (Loss) [Member]
Energy And Weather Contracts [Member]
Jun. 30, 2011
Other Income (Loss) [Member]
Energy And Weather Contracts [Member]
Jan. 20, 2011
Other Income (Loss) [Member]
Platinum Warrant [Member]
Jun. 30, 2012
Other Income (Loss) [Member]
Platinum Warrant [Member]
Jun. 30, 2011
Other Income (Loss) [Member]
Platinum Warrant [Member]
Derivative Instruments, Gain (Loss) [Line Items]                                                              
Amount of gain (loss) recognized on derivatives $ 9,208 $ (4,600) $ (18,476) $ 906 $ (2,847) $ (7,693) $ (1,817) $ (8,347) $ (24) $ 420 $ 534 $ 1,142 $ (2,183) [1] $ 9,208 [1] $ 1,369 [1] $ 17,007 [1] $ 1,899 [2] $ (7,752) [2] $ (2,349) [2] $ (21,152) [2] $ 376 [3] $ (212) [3] $ 513 [3] $ (648) [3] $ 11,987 $ 1,429 $ (16,726) $ 9,929 $ 3,000 $ 0 $ 2,975
[1] Contracts used to manage foreign currency risks in underwriting and non-investment operations.
[2] Contracts used to manage foreign currency risks in investment operations.
[3] Contracts used to manage foreign currency risks in energy and risk operations.