v2.4.0.6
Changes in Fair Value of Level 3 Financial Assets And Liabilities (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance $ 150,258 $ 121,451 $ 130,445 $ 38,958
Net income 14,164 13,819 25,785 67,945
Other comprehensive income (501) (1,348) 3,070 (1,725)
Purchases and issuances 9,941 11,970 25,051 41,370
Sales and settlements (2,585) (15,658) (13,074) (16,314)
Net transfers into (out of) Level 3 4,973 0 4,973 0
Ending Balance 176,250 130,234 176,250 130,234
Other investments
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance 15,103 22,008 14,588 21,514
Net income 1,491 0 (2,861) 661
Other comprehensive income 0 (1,348) 4,535 (1,725)
Purchases and issuances 315 5,672 1,062 6,538
Sales and settlements (2,585) (5,128) (3,000) (5,784)
Net transfers into (out of) Level 3 0 0 0 0
Ending Balance 14,324 21,204 14,324 21,204
Life settlement contracts
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance 151,092 108,710 131,387 22,155
Net income 10,758 17,188 26,174 75,209
Purchases and issuances 9,626 6,298 23,989 34,832
Sales and settlements 0 (10,530) (10,074) (10,530)
Net transfers into (out of) Level 3 0 0 0 0
Ending Balance 171,476 121,666 171,476 121,666
Life settlement contract profit commission
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance (11,465) (9,267) (12,022) (4,711)
Net income 1,915 (3,369) 2,472 (7,925)
Net transfers into (out of) Level 3 0 0 0 0
Ending Balance (9,550) (12,636) (9,550) (12,636)
Derivatives
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance (4,472)   (3,508)  
Other comprehensive income (501)   (1,465)  
Net transfers into (out of) Level 3 4,973   4,973  
Ending Balance $ 0   $ 0