Note 6 - Consolidated K-Series (Details) - Geographic Concentrations of Credit Risk (Multi-Family Loans Held in Securitization Trusts [Member])	9 Months Ended	12 Months Ended
Sep. 30, 2014	Dec. 31, 2013
California [Member]
Concentration Risk [Line Items]
Geographic concentrations	13.30%	14.00%
Texas [Member]
Concentration Risk [Line Items]
Geographic concentrations	12.20%	13.70%
New York [Member]
Concentration Risk [Line Items]
Geographic concentrations	7.50%	7.20%
Florida [Member]
Concentration Risk [Line Items]
Geographic concentrations	6.80%	6.50%
Washington [Member]
Concentration Risk [Line Items]
Geographic concentrations	5.40%	5.30%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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