Note 5 - Investment Securities - Available For Sale (Details) - Short-term Investment by Bond Maturities (USD $)	Jun. 30, 2013	Dec. 31, 2012
Within 3 Months [Member]
Corporate bond maturities
Cost	$ 15,106,659	$ 3,053,740
Fair value	15,041,480	3,002,350
Between 3-12 Months [Member]
Corporate bond maturities
Cost	27,813,952	5,110,487
Fair value	27,665,289	5,035,270
Bond maturities [Member]
Corporate bond maturities
Cost	42,920,611	8,164,227
Fair value	$ 42,706,769	$ 8,037,620