Note 8 - Fair Value Measurements (Details) - Discounted Cash Flow Model Values	Jun. 30, 2013	Dec. 31, 2012
Discounted Cash Flow Model Values [Abstract]
Time-to-liquidity (months)	24 months	24 months
Expected return (based on the requisite treasury rate, plus a contractual penalty rate)	2.30%	1.80%
Discount rate (based on the requisite LIBOR, the cost of debt and a liquidity risk premium)	3.1%-7.9%, depending on the credit-rating of the security	2.5%-7.3%, depending on the credit-rating of the security