v2.4.0.6

Fair Value Measurement of Financial Assets and Financial Liabilities on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2012
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Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | $ 2,052,226
Fair Value of liabilities | 297,819
U.S. treasury securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 48,341
U.S. government agencies |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 46,305
Municipal bonds |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 265,011
Commercial mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 10,209
Agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 332,027
Non-agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 6,759
Equity securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 18,318
Short term investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 485
Other investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 14,324
Life settlement contracts |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 171,476
Equity securities sold but not yet purchased, market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 43
Fixed maturity securities sold but not yet purchased , market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 57,155
Securities sold under agreements to repurchase, at contract value |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 226,098
Life settlement contract profit commission |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 9,550
Derivatives |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 4,973
Corporate Bonds | Finance |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 773,474
Corporate Bonds | Industrial |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 330,269
Corporate Bonds | Utilities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 35,228
Fair Value, Inputs, Level 1 |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 67,144
Fair Value of liabilities | 57,198
Fair Value, Inputs, Level 1 | U.S. treasury securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 48,341
Fair Value, Inputs, Level 1 | U.S. government agencies |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Municipal bonds |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Finance |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Industrial |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Utilities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Commercial mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Non-agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Equity securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 18,318
Fair Value, Inputs, Level 1 | Short term investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 485
Fair Value, Inputs, Level 1 | Other investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Life settlement contracts |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 1 | Equity securities sold but not yet purchased, market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 43
Fair Value, Inputs, Level 1 | Fixed maturity securities sold but not yet purchased , market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 57,155
Fair Value, Inputs, Level 1 | Securities sold under agreements to repurchase, at contract value |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 1 | Life settlement contract profit commission |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 1 | Derivatives |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 2 |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 1,799,282
Fair Value of liabilities | 231,071
Fair Value, Inputs, Level 2 | U.S. treasury securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 2 | U.S. government agencies |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 46,305
Fair Value, Inputs, Level 2 | Municipal bonds |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 265,011
Fair Value, Inputs, Level 2 | Commercial mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 10,209
Fair Value, Inputs, Level 2 | Agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 332,027
Fair Value, Inputs, Level 2 | Non-agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 6,759
Fair Value, Inputs, Level 2 | Equity securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 2 | Short term investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 2 | Other investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 2 | Life settlement contracts |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 2 | Equity securities sold but not yet purchased, market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 2 | Securities sold under agreements to repurchase, at contract value |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 226,098
Fair Value, Inputs, Level 2 | Life settlement contract profit commission |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 2 | Derivatives |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 4,973
Fair Value, Inputs, Level 2 | Corporate Bonds | Finance |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 773,474
Fair Value, Inputs, Level 2 | Corporate Bonds | Industrial |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 330,269
Fair Value, Inputs, Level 2 | Corporate Bonds | Utilities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 35,228
Fair Value, Inputs, Level 3 |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 185,800
Fair Value of liabilities | 9,550
Fair Value, Inputs, Level 3 | U.S. treasury securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | U.S. government agencies |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Municipal bonds |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Finance |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Industrial |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Utilities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Commercial mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Non-agency, residential mortgage backed securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Equity securities |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Short term investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 0
Fair Value, Inputs, Level 3 | Other investments |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 14,324
Fair Value, Inputs, Level 3 | Life settlement contracts |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair value of assets | 171,476
Fair Value, Inputs, Level 3 | Equity securities sold but not yet purchased, market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 3 | Fixed maturity securities sold but not yet purchased , market |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 3 | Securities sold under agreements to repurchase, at contract value |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 0
Fair Value, Inputs, Level 3 | Life settlement contract profit commission |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | 9,550
Fair Value, Inputs, Level 3 | Derivatives |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |
Fair Value of liabilities | $ 0

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- Definition This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + 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 (a) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + 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 (a) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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