Information for Financial Instruments on Which Fair Value Option was Elected (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	$ (283,576)		$ (587,726)
Fair value of financial instruments more than one day past due	57,837	[1]	36,153	[1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due	(176,379)	[1]	(73,335)	[1]
Loans And Receivables
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(533)		(292)
Corporate Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(281,254)		(586,450)
Fair value of financial instruments more than one day past due	57,837	[1]	35,322	[1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due	(176,379)	[1]	(73,291)	[1]
Corporate Bonds
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(1,789)		(984)
Fair value of financial instruments more than one day past due			831	[1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due			$ (44)	[1]

[1] Corporate Loans and Corporate Bonds within CLO assets are classified as past due if contractual payments are more than one day past due.