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Fair Value Measurements (Details 4) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2012 | Jun. 30, 2011
Net investment income [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses included in earnings | $ 88 | $ (3,321) | $ 40 | $ (3,371)
Realized gains or (losses) and other settlements on credit derivative contracts [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses and other settlements on credit derivative contracts | 3,072 | 4,224 | 6,326 | 9,547
Unrealized gains or (losses) on credit derivative contracts [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses and other settlements on credit derivative contracts | (10,489) | 20,063 | (20,964) | 5,837
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date | (10,613) | 17,719 | (26,647) | 536
Derivative products revenue (interest rate swaps) [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses and other settlements on credit derivative contracts | (112,904) | (76,255) | (45,035) | (66,432)
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date | (107,861) | (83,407) | (46,263) | (69,607)
Variable Interest Entity [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses and other settlements on credit derivative contracts | 173,145 | 374,333 | 120,431 | 312,467
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date | 173,145 | 374,333 | 120,912 | 312,467
Other income [Member] |  |  |  |
Summary of Gains and losses realized and unrealized relating to Level 3 assets and liabilities included in earnings |  |  |  |
Gains or losses and other settlements on credit derivative contracts | 38,799 | 3,491 | 99,723 | 21,312
Changes in unrealized gains or losses relating to the assets and liabilities still held at the reporting date | $ (231) | $ 3,491 | $ (987) | $ 21,312

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- Definition This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets) in investment income; the fair value of which assets was or is measured on a recurring basis using significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(1) -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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