Note 6 - Consolidated K-Series (Details) - Geographic Concentrations of Credit Risk (Multi-Family Loans Held in Securitization Trusts [Member])
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Texas [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 14.00% 14.00%
California [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 13.70% 13.60%
New York [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 7.20% 6.80%
Florida [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 6.50% 7.40%
Washington [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 5.30% 5.00%
Georgia [Member]
   
Concentration Risk [Line Items]    
Geographic concentrations 4.40% 5.40%