Note 5 - Credit Quality and the Allowance for Loan and Lease Losses (Detail) - Aging Analysis of the Loan Portfolio (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Recorded Balance of Loans Past Due:
Total Loans	$ 244,064,000	$ 243,741,000	$ 220,096,000
Accruing Troubled Debt Restructurings			743,000
Construction and Land Development Loans [Member]
Recorded Balance of Loans Past Due:
30-59 Days			133,000
Total Past Due			133,000
Loans in Current Payment Status	12,711,000	11,995,000	14,972,000
Total Loans	12,711,000	11,995,000	15,105,000
Loans 90+ Days Past Due and Accruing1	0	0
Accruing Troubled Debt Restructurings	0	0	200,000
Loans in Non-accrual Status	751,000	555,000	279,000
Commercial Real Estate Owner Occupied [Member]
Recorded Balance of Loans Past Due:
30-59 Days		55,000	977,000
60-89 Days	894,000	916,000
90+ Days	758,000	820,000	594,000
Total Past Due	1,652,000	1,791,000	1,571,000
Loans in Current Payment Status	64,690,000	69,237,000	68,404,000
Total Loans	66,342,000	71,028,000	69,975,000
Loans 90+ Days Past Due and Accruing1	0	0
Accruing Troubled Debt Restructurings	11,000	13,000
Loans in Non-accrual Status	3,626,000	3,779,000	1,756,000
Commercial Real Estate Non Owner Occupied [Member]
Recorded Balance of Loans Past Due:
Loans in Current Payment Status	69,640,000	69,361,000	60,473,000
Total Loans	69,640,000	69,361,000	60,473,000
Loans 90+ Days Past Due and Accruing1	0	0
Accruing Troubled Debt Restructurings	0	0
Loans in Non-accrual Status	827,000	845,000	108,000
Residential Real Estate Loans [Member]
Recorded Balance of Loans Past Due:
30-59 Days	377,000	325,000
60-89 Days	76,000
90+ Days	158,000	343,000	459,000
Total Past Due	611,000	668,000	459,000
Loans in Current Payment Status	29,565,000	30,373,000	31,608,000
Total Loans	30,176,000	31,041,000	32,067,000
Loans 90+ Days Past Due and Accruing1	0	0
Accruing Troubled Debt Restructurings	706,000	709,000
Loans in Non-accrual Status	912,000	842,000	1,640,000
All Other Real Estate Loans [Member]
Recorded Balance of Loans Past Due:
Loans in Current Payment Status	12,686,000	8,348,000	1,889,000
Total Loans	12,686,000	8,348,000	1,889,000
Loans 90+ Days Past Due and Accruing1	0	0
Accruing Troubled Debt Restructurings	0	0
Loans in Non-accrual Status	25,000	29,000
Commercial and Industrial Loans [Member]
Recorded Balance of Loans Past Due:
30-59 Days	262,000	620,000	240,000
60-89 Days	6,000	44,000	112,000
90+ Days	866,000	227,000	205,000
Total Past Due	1,134,000	891,000	557,000
Loans in Current Payment Status	47,316,000	48,463,000	36,400,000
Total Loans	48,450,000	49,354,000	36,957,000
Loans 90+ Days Past Due and Accruing1		0
Accruing Troubled Debt Restructurings		0
Loans in Non-accrual Status	2,851,000	3,018,000	1,692,000
Consumer and All Other Loans and Lease Financing [Member]
Recorded Balance of Loans Past Due:
30-59 Days		69,000	8,000
60-89 Days	9,000
Total Past Due	9,000	69,000	8,000
Loans in Current Payment Status	4,050,000	2,545,000	3,622,000
Total Loans	4,059,000	2,614,000	3,630,000
Loans 90+ Days Past Due and Accruing1		0
Accruing Troubled Debt Restructurings	0	0
Total [Member]
Recorded Balance of Loans Past Due:
30-59 Days	639,000	1,069,000	1,358,000
60-89 Days	985,000	960,000	112,000
90+ Days	1,782,000	1,390,000	1,258,000
Total Past Due	3,406,000	3,419,000	2,728,000
Loans in Current Payment Status	240,658,000	240,322,000	217,368,000
Total Loans	244,064,000	243,741,000	220,096,000
Loans 90+ Days Past Due and Accruing1		0
Accruing Troubled Debt Restructurings	717,000	722,000	200,000
Loans in Non-accrual Status	$ 8,992,000	$ 9,068,000	$ 5,475,000