Note 2 - Investment Securities (Detail) - Unrealized Loss Positions of Available for Sale Securities (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Estimated Fair Value, Less than 12 Months		$ 12,529
Unrealized Loss, Less than 12 Months		(126)
Estimated Fair Value, 12 Months or More	8,696	725
Unrealized Loss, 12 Months or More	(90)	(5)
Estimated Fair Value, Total	8,696	13,254
Unrealized Loss, Total	(90)	(131)
US Government Agency Securities [Member]
Estimated Fair Value, Less than 12 Months		6,201
Unrealized Loss, Less than 12 Months		(16)
Estimated Fair Value, 12 Months or More	3,400
Unrealized Loss, 12 Months or More	(32)
Estimated Fair Value, Total	3,400	6,201
Unrealized Loss, Total	(32)	(16)
Mortgage-Backed Securities [Member]
Estimated Fair Value, Less than 12 Months		2,957
Unrealized Loss, Less than 12 Months		(14)
Estimated Fair Value, 12 Months or More	3,701	725
Unrealized Loss, 12 Months or More	(35)	(5)
Estimated Fair Value, Total	3,701	3,682
Unrealized Loss, Total	(35)	(19)
Municipal Securities [Member]
Estimated Fair Value, Less than 12 Months		3,371
Unrealized Loss, Less than 12 Months		(96)
Estimated Fair Value, 12 Months or More	1,595
Unrealized Loss, 12 Months or More	(23)
Estimated Fair Value, Total	1,595	3,371
Unrealized Loss, Total	$ (23)	$ (96)