Note 3 - Investment Securities (Details) (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Note 3 - Investment Securities (Details) [Line Items]
Available-for-sale Securities, Gross Realized Gains	$ 179,000	$ 527,000
Available-for-sale Securities, Gross Realized Losses	5,000	0
Proceeds from Sale of Available-for-sale Securities, Equity	29,374,000	24,877,000
Available-for-sale Securities Pledged as Collateral	3,608,000
Public Deposits [Member]
Note 3 - Investment Securities (Details) [Line Items]
Available-for-sale Securities Pledged as Collateral	33,234,000
Borrowing Facilities of Federal Home Loan Bank of San Francisco [Member]
Note 3 - Investment Securities (Details) [Line Items]
Available-for-sale Securities Pledged as Collateral	$ 16,765,000
Unrealized Loss Position Less Than 12 Months [Member]
Note 3 - Investment Securities (Details) [Line Items]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	93