Internal CRE Debt and Preferred Equity Ratings (Detail) (Commercial Mortgage, USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Transaction to Real Estate Investments [Line Items]
Performing Loans	$ 1,612,900		$ 1,555,750
Internal Ratings Watch List Loans	31,473		31,473
Senior Mortgages
Transaction to Real Estate Investments [Line Items]
Performing Loans	312,372		644,039
Internal Ratings Watch List Loans	25,473	[1]	25,473	[2]
Senior Securitized Mortgages
Transaction to Real Estate Investments [Line Items]
Performing Loans	399,541	[3]
Subordinated Notes
Transaction to Real Estate Investments [Line Items]
Performing Loans	15,965		41,059
Mezzanine Loans
Transaction to Real Estate Investments [Line Items]
Performing Loans	635,253		620,883
Internal Ratings Watch List Loans	6,000		6,000
Preferred Equity Interests
Transaction to Real Estate Investments [Line Items]
Performing Loans	$ 249,769		$ 249,769

[1] (2) Includes approximately $13 million related to one loan on non accrual status.

[2] (1) Includes approximately $13 million related to one loan on non accrual status.

[3] (1) Assets of consolidated VIE.