v2.4.0.6

Derivative Instruments (Consolidated Balance Sheets And Fair Value Of The Principal Derivative Instruments) (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | $ 85,752 |  | $ 54,382 |
Gross Amounts Offset in the Balance Sheet | 32,073 |  | 16,001 |
Net Amounts of Assets Presented in the Balance Sheet | 53,679 |  | 38,381 |
Collateral | 248 |  | 3,596 |
Net Amount | 53,431 |  | 34,785 |
Derivative Liabilities |  |  |  |
Gross Amounts of Recognized Liabilities | 50,162 |  | 38,471 |
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 20,146 |  | 19,213 |
Net Amounts of Liabilities Presented in the Balance Sheet | 30,016 |  | 19,258 |
Collateral | 1,546 |  | 41 |
Net Amount | 28,470 |  | 19,217 |
Other Assets [Member] | Interest Rate Futures [Member] |  |  |  |
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | 429 |  | 441 |
Gross Amounts Offset in the Balance Sheet | 0 |  | 0 |
Net Amounts of Assets Presented in the Balance Sheet | 429 |  | 441 |
Collateral | 0 |  | 0 |
Net Amount | 429 |  | 441 |
Other Assets [Member] | Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member] |  |  |  |
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | 8,070 | [1] | 7,191 | [1]
Gross Amounts Offset in the Balance Sheet | 0 | [1] | 0 | [1]
Net Amounts of Assets Presented in the Balance Sheet | 8,070 | [1] | 7,191 | [1]
Collateral | 0 | [1] | 0 | [1]
Net Amount | 8,070 | [1] | 7,191 | [1]
Other Assets [Member] | Foreign Currency Forward Contracts, Investment Operations [Member] |  |  |  |
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | 6,541 | [2] | 2,534 | [2]
Gross Amounts Offset in the Balance Sheet | 5,880 | [2] | 2,296 | [2]
Net Amounts of Assets Presented in the Balance Sheet | 661 | [2] | 238 | [2]
Collateral | 0 | [2] | 0 | [2]
Net Amount | 661 | [2] | 238 | [2]
Other Assets [Member] | Credit Default Swap [Member] |  |  |  |
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | 547 |  | 784 |
Gross Amounts Offset in the Balance Sheet | 299 |  | 333 |
Net Amounts of Assets Presented in the Balance Sheet | 248 |  | 451 |
Collateral | 248 |  | 310 |
Net Amount | 0 |  | 141 |
Other Assets [Member] | Energy And Weather Contracts [Member] |  |  |  |
Derivative Assets |  |  |  |
Gross Amounts of Recognized Assets | 70,165 |  | 43,432 |
Gross Amounts Offset in the Balance Sheet | 25,894 |  | 13,372 |
Net Amounts of Assets Presented in the Balance Sheet | 44,271 |  | 30,060 |
Collateral | 0 |  | 3,286 |
Net Amount | 44,271 |  | 26,774 |
Other Liabilities [Member] | Interest Rate Futures [Member] |  |  |  |
Derivative Liabilities |  |  |  |
Gross Amounts of Recognized Liabilities | 30 |  | 41 |
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 0 |  | 0 |
Net Amounts of Liabilities Presented in the Balance Sheet | 30 |  | 41 |
Collateral | 30 |  | 41 |
Net Amount | 0 |  | 0 |
Other Liabilities [Member] | Foreign Currency Forward Contracts, Underwriting and Non-investment Operations [Member] |  |  |  |
Derivative Liabilities |  |  |  |
Gross Amounts of Recognized Liabilities | 4,227 | [1] | 4,173 | [1]
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 0 | [1] | 0 | [1]
Net Amounts of Liabilities Presented in the Balance Sheet | 4,227 | [1] | 4,173 | [1]
Collateral | 0 | [1] | 0 | [1]
Net Amount | 4,227 | [1] | 4,173 | [1]
Other Liabilities [Member] | Foreign Currency Forward Contracts, Energy And Risk Operations [Member] |  |  |  |
Derivative Liabilities |  |  |  |
Gross Amounts of Recognized Liabilities | 211 | [3] | 579 | [3]
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 58 | [3] | 53 | [3]
Net Amounts of Liabilities Presented in the Balance Sheet | 153 | [3] | 526 | [3]
Collateral | 153 | [3] | 0 | [3]
Net Amount | 0 | [3] | 526 | [3]
Other Liabilities [Member] | Energy And Weather Contracts [Member] |  |  |  |
Derivative Liabilities |  |  |  |
Gross Amounts of Recognized Liabilities | 45,694 |  | 33,678 |
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 20,088 |  | 19,160 |
Net Amounts of Liabilities Presented in the Balance Sheet | 25,606 |  | 14,518 |
Collateral | 1,363 |  | 0 |
Net Amount | $ 24,243 |  | $ 14,518 |
[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.

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