Note 6 - Consolidated K-Series (Details) - Condensed Statement of Operations of Consolidated K-Series (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Condensed Income Statements, Captions [Line Items]
Interest expense	$ 1,230	$ 1,598	$ 4,102	$ 5,045
Net interest income	19,320	15,207	59,028	42,090
Unrealized gain on multi-family loans and debt held in securitization trusts, net	18,115	6,338	43,060	22,370
Consolidated K-Series [Member]
Condensed Income Statements, Captions [Line Items]
Interest income	75,891	61,179	226,336	160,981
Interest expense	69,310	56,199	207,167	148,107
Net interest income	6,581	4,980	19,169	12,874
Unrealized gain on multi-family loans and debt held in securitization trusts, net	18,115	6,338	43,060	22,370
Net Income	$ 24,696	$ 11,318	$ 62,229	$ 35,244