Note 3 - Trading Account Assets (Details) - Trading Accounts Credit Ratings (Credit Concentration Risk [Member], Trading, Municipal Bonds [Member])	12 Months Ended
	Dec. 31, 2013
Moody's [Member] | Not Rated [Member]
bonds
Trading accounts credit ratings	100.00%
Standard & Poor's [Member]
bonds
Trading accounts credit ratings	100.00%
Moody's, Aaa Rating [Member]
bonds
Trading accounts credit ratings	13.00%
Moody's, Aa1 - A3 Rating [Member]
bonds
Trading accounts credit ratings	67.00%
Moody's, Baa1 Rating [Member]
bonds
Trading accounts credit ratings	2.00%
Not Rated [Member]
bonds
Trading accounts credit ratings	18.00%
Standard & Poor's, AAA Rating [Member]
bonds
Trading accounts credit ratings	18.00%
Standard & Poor's, AA+ Rating [Member]
bonds
Trading accounts credit ratings	13.00%
Standard & Poor's, Aa - A- [Member]
bonds
Trading accounts credit ratings	57.00%
Not Rated [Member]
bonds
Trading accounts credit ratings	12.00%