v2.4.0.6
Information for Financial Instruments on Which Fair Value Option was Elected (Detail) (USD $)
Jun. 30, 2012
Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Uncollected principal balance on financial instruments that exceeded fair value total $ (842,890) $ (684,018)
Fair value of financial instruments more than one day past due 61,771 [1] 25,134 [1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due (71,836) [1] (32,040) [1]
Loans And Receivables
    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Uncollected principal balance on financial instruments that exceeded fair value total 1,738 (162)
Corporate Loans
    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Uncollected principal balance on financial instruments that exceeded fair value total (837,123) (674,496)
Fair value of financial instruments more than one day past due 61,771 [1] 17,574 [1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due (71,836) [1] (29,384) [1]
Corporate Bonds
    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Uncollected principal balance on financial instruments that exceeded fair value total (7,505) (9,360)
Fair value of financial instruments more than one day past due   7,560 [1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due   $ (2,656) [1]
[1] Past due Corporate Loans and Corporate Bonds within CLO assets are classified as past due if contractual payments are more than one day past due.