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 6 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Jun. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance $ 141,795 $ 80,609 $ 130,445 $ 38,958
Net income 7,638 30,164 11,621 54,067
Other comprehensive income (877) (875) 3,571 (377)
Purchases and issuances 11,812 11,968 15,110 29,459
Sales and settlements (10,110) (415) (10,489) (656)
Net transfers into (out of) Level 3            
Ending Balance 150,258 121,451 150,258 121,451
Other investments
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance 14,865 22,512 14,588 21,514
Net income (403)   (4,352) 661
Other comprehensive income   (875) 4,535 (377)
Purchases and issuances 677 786 747 866
Sales and settlements (36) (415) (415) (656)
Net transfers into (out of) Level 3            
Ending Balance 15,103 22,008 15,103 22,008
Life settlement contracts
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance 142,575 63,686 131,387 22,155
Net income 7,456 33,842 15,416 57,962
Purchases and issuances 11,135 11,182 14,363 28,593
Sales and settlements (10,074)   (10,074)  
Net transfers into (out of) Level 3            
Ending Balance 151,092 108,710 151,092 108,710
Life settlement contract profit commission
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance (12,050) (5,589) (12,022) (4,711)
Net income 585 (3,678) 557 (4,556)
Net transfers into (out of) Level 3            
Ending Balance (11,465) (9,267) (11,465) (9,267)
Derivatives
        
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]        
Beginning Balance (3,595)   (3,508)  
Other comprehensive income (877)   (964)  
Net transfers into (out of) Level 3          
Ending Balance $ (4,472)   $ (4,472)