Note 2 - Investment Securities (Detail) - Investment Securities With Unrealized Losses Not Recognized In Income (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
More 12 Months Unrealized Losses	$ 856
US Government-sponsored Enterprises Debt Securities [Member]
Less 12 Months Fair Value	26,433	13,494
Less 12 Months Unrealized Losses	66	15
Total Fair Value	26,433	13,494
Total Unrealized Losses	66	15
US States and Political Subdivisions Debt Securities [Member]
Less 12 Months Fair Value	17,199	2,913
Less 12 Months Unrealized Losses	174	20
More 12 Months Fair Value		6,886
More 12 Months Unrealized Losses		65
Total Fair Value	17,199	9,799
Total Unrealized Losses	174	85
Residential Mortgage Backed Securities [Member]
Less 12 Months Fair Value	39,659	56,249
Less 12 Months Unrealized Losses	256	196
Total Fair Value	39,659	56,249
Total Unrealized Losses	256	196
Mortgage Funds and Equity Securities [Member]
Less 12 Months Fair Value	299
Less 12 Months Unrealized Losses	2
Total Fair Value	299
Total Unrealized Losses	2
Corporate Debt Securities [Member]
More 12 Months Fair Value	4,994	4,299
More 12 Months Unrealized Losses	856	1,537
Total Fair Value	4,994	4,299
Total Unrealized Losses	856	1,537
Total [Member]
Less 12 Months Fair Value	83,590	72,656
Less 12 Months Unrealized Losses	498	231
More 12 Months Fair Value	4,994	11,185
More 12 Months Unrealized Losses	856	1,602
Total Fair Value	88,584	83,841
Total Unrealized Losses	$ 1,354	$ 1,833