Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Summary of Loans Past Due 90 Days or More and Impaired Loans (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Summary of Loans Past Due 90 Days or More and Impaired Loans [Abstract]
Loans past due 90 days or more and still accruing	$ 163		$ 568		$ 190
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees	0.03%		0.10%		0.03%
Accruing restructured loans	6,145		5,732		6,191
Impaired loans with no valuation allowance	10,139		16,263		10,372
Impaired loans with a valuation allowance	2,463		995		2,613
Total impaired loans	12,602		17,258		12,985
Valuation allowance	(280)		(273)		(624)
Impaired loans, net of allowance	12,322		16,985		12,361
Average recorded investment in impaired loans(1)	13,075	[1],[2]	17,935	[1]	16,654	[1],[2]
Interest income recognized on impaired loans, after designation as impaired	$ 99	[2]	$ 10		$ 267	[2]

[1] Recorded investment includes principal net of unearned interest and deferred fees and costs, and accrued interest.

[2] Only classes with impaired loans are shown.