Note 4 - Allowance for Loan Losses (Detail) - Allowance for Loan Losses (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Construction loans:
Beginning balance	$ 3,979	$ 5,228
Charge-offs	(1,616)	(2,474)
Recoveries	19	3
Provisions	1,408	1,222
Ending Balance	3,790	3,979
Ending balance: individually evaluated for impairment	208	629
Ending balance: collectively evaluated for impairment	3,582	3,350
Ending balance	274,937	249,079
Ending balance: individually evaluated for impairment	15,630	15,919
Ending balance: collectively evaluated for impairment	259,307	233,160
Construction Residential [Member]
Construction loans:
Beginning balance	90	121
Charge-offs		(150)
Provisions	27	119
Ending Balance	117	90
Ending balance: collectively evaluated for impairment	117	90
Ending balance	5,036	3,695
Ending balance: collectively evaluated for impairment	5,036	3,695
Land Acquistion, Development and Commercial [Member]
Construction loans:
Beginning balance	953	1,802
Charge-offs	(519)	(1,500)
Provisions	377	651
Ending Balance	811	953
Ending balance: individually evaluated for impairment		249
Ending balance: collectively evaluated for impairment	811	704
Ending balance	20,198	23,911
Ending balance: individually evaluated for impairment	3,632	2,975
Ending balance: collectively evaluated for impairment	16,566	20,936
Real Estate Residential [Member]
Construction loans:
Beginning balance	538	785
Charge-offs	(151)	(170)
Provisions	338	77
Ending Balance	725	538
Ending balance: individually evaluated for impairment	137
Ending balance: collectively evaluated for impairment	588	538
Ending balance	69,691	58,070
Ending balance: individually evaluated for impairment	810	714
Ending balance: collectively evaluated for impairment	68,881	57,356
Real Estate Commercial [Member]
Construction loans:
Beginning balance	1,314	1,556
Charge-offs	(478)	(356)
Recoveries	18
Provisions	200	114
Ending Balance	1,054	1,314
Ending balance: individually evaluated for impairment	71	292
Ending balance: collectively evaluated for impairment	983	1,022
Ending balance	109,302	102,312
Ending balance: individually evaluated for impairment	10,157	11,588
Ending balance: collectively evaluated for impairment	99,145	90,724
Commercial, Industrial and Agricultural [Member]
Construction loans:
Beginning balance	628	702
Charge-offs	(71)	(139)
Provisions	(98)
Ending Balance	459	628
Ending balance: collectively evaluated for impairment	459	628
Ending balance	42,382	36,297
Ending balance: individually evaluated for impairment	916
Ending balance: collectively evaluated for impairment	41,466	36,297
Equity Lines [Member]
Construction loans:
Beginning balance	313	222
Charge-offs	(393)	(158)
Provisions	466	249
Ending Balance	386	313
Ending balance: individually evaluated for impairment		88
Ending balance: collectively evaluated for impairment	386	225
Ending balance	20,504	19,018
Ending balance: individually evaluated for impairment	115	642
Ending balance: collectively evaluated for impairment	20,389	18,376
Consumer [Member]
Construction loans:
Beginning balance	143	40
Charge-offs	(4)	(1)
Recoveries	1	3
Provisions	5	101
Ending Balance	145	143
Ending balance: collectively evaluated for impairment	145	143
Ending balance	7,824	5,776
Ending balance: collectively evaluated for impairment	7,824	5,776
Unallocated [Member]
Construction loans:
Provisions	93
Ending Balance	93
Ending balance: collectively evaluated for impairment	$ 93