Note 5 - Agency Securities, Available for Sale (Detail)	Mar. 31, 2013	Dec. 31, 2012
Percentage of Portfolio Invested in Agency Securities	88.70%	89.50%
Agency Securities, Fixed Rate Securities, Weighted Average Coupon	3.14%	3.14%
Percentage of Portfolio Invested in Non-Agency Securities	11.30%	10.50%

Agency Securities, fixed rate securities, weighted average coupon.

No definition available.

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