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Note 3 - Loans and Allowance for Loan Losses (Details) - Impaired Loans - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	$ 9,541,000		$ 9,541,000		$ 8,255,000
Recorded principal balance, with no related allowance	8,654,000		8,654,000		5,552,000
Average recorded principal balance, with no related allowance	8,824,000	$ 11,800,000	7,119,000	$ 7,838,000
Unpaid contractual principal balance, with a related allowance	15,431,000		15,431,000		42,757,000
Recorded principal balance, with a related allowance	10,393,000		10,393,000		42,304,000
Related allowance	1,827,000		1,827,000		10,152,000
Average recorded principal balance, with a related allowance	10,843,000	29,611,000	26,041,000	30,432,000
Upaid contractual principal balance	24,972,000		24,972,000		51,012,000
Recorded principal balance	19,047,000		19,047,000		47,856,000
Average recorded principal balance	19,667,000	41,411,000	33,160,000	38,270,000
Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	8,217,000		8,217,000		4,019,000
Recorded principal balance, with no related allowance	7,732,000		7,732,000		4,010,000
Average recorded principal balance, with no related allowance	7,205,000	0	5,531,000	0
Unpaid contractual principal balance, with a related allowance	318,000		318,000		1,516,000
Recorded principal balance, with a related allowance	318,000		318,000		1,502,000
Related allowance	15,000		15,000		605,000
Average recorded principal balance, with a related allowance	896,000	0	1,286,000	0
Upaid contractual principal balance	8,535,000		8,535,000		5,535,000
Recorded principal balance	8,050,000		8,050,000		5,512,000
Average recorded principal balance	8,101,000	0	6,817,000	0
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	7,928,000		7,928,000		6,904,000
Recorded principal balance, with no related allowance	7,729,000		7,729,000		4,801,000
Average recorded principal balance, with no related allowance	7,919,000	10,605,000	6,298,000	6,649,000
Unpaid contractual principal balance, with a related allowance	15,071,000		15,071,000		40,448,000
Recorded principal balance, with a related allowance	10,106,000		10,106,000		40,220,000
Related allowance	1,657,000		1,657,000		9,374,000
Average recorded principal balance, with a related allowance	10,552,000	27,430,000	25,257,000	28,149,000
Upaid contractual principal balance	22,999,000		22,999,000		47,352,000
Recorded principal balance	17,835,000		17,835,000		45,021,000
Average recorded principal balance	18,471,000	38,035,000	31,555,000	34,798,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,893,000		1,893,000		1,170,000
Recorded principal balance, with no related allowance	1,893,000		1,893,000		1,164,000
Average recorded principal balance, with no related allowance	1,908,000	691,000	1,729,000	525,000
Unpaid contractual principal balance, with a related allowance	470,000		470,000		5,299,000
Recorded principal balance, with a related allowance	413,000		413,000		5,226,000
Related allowance	271,000		271,000		1,578,000
Average recorded principal balance, with a related allowance	436,000	3,087,000	2,816,000	2,142,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	0		0		540,000
Recorded principal balance, with no related allowance	0		0		209,000
Average recorded principal balance, with no related allowance	0	111,000	101,000	232,000
Unpaid contractual principal balance, with a related allowance	2,275,000		2,275,000		2,000,000
Recorded principal balance, with a related allowance	1,920,000		1,920,000		2,000,000
Related allowance	308,000		308,000		151,000
Average recorded principal balance, with a related allowance	2,052,000	3,049,000	2,026,000	3,536,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	302,000		302,000		3,609,000
Recorded principal balance, with no related allowance	103,000		103,000		1,901,000
Average recorded principal balance, with no related allowance	113,000	9,227,000	1,032,000	4,981,000
Unpaid contractual principal balance, with a related allowance	6,377,000		6,377,000		15,745,000
Recorded principal balance, with a related allowance	1,824,000		1,824,000		15,674,000
Related allowance	494,000		494,000		2,200,000
Average recorded principal balance, with a related allowance	1,959,000	2,238,000	8,778,000	1,869,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	5,733,000		5,733,000		1,210,000
Recorded principal balance, with no related allowance	5,733,000		5,733,000		1,210,000
Average recorded principal balance, with no related allowance	5,747,000	576,000	3,204,000	911,000
Unpaid contractual principal balance, with a related allowance	4,897,000		4,897,000		16,033,000
Recorded principal balance, with a related allowance	4,897,000		4,897,000		15,949,000
Related allowance	194,000		194,000		4,779,000
Average recorded principal balance, with a related allowance	4,926,000	17,377,000	10,371,000	18,819,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	0		0		375,000
Recorded principal balance, with no related allowance	0		0		317,000
Average recorded principal balance, with no related allowance	151,000	0	232,000	0
Unpaid contractual principal balance, with a related allowance	1,052,000		1,052,000		1,371,000
Recorded principal balance, with a related allowance	1,052,000		1,052,000		1,371,000
Related allowance	390,000		390,000		666,000
Average recorded principal balance, with a related allowance	1,179,000	1,679,000	1,266,000	1,783,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	6,738,000		6,738,000		2,512,000
Recorded principal balance, with no related allowance	6,457,000		6,457,000		2,505,000
Average recorded principal balance, with no related allowance	6,047,000	0	4,253,000	0
Unpaid contractual principal balance, with a related allowance	142,000		142,000		1,516,000
Recorded principal balance, with a related allowance	142,000		142,000		1,502,000
Related allowance	9,000		9,000		605,000
Average recorded principal balance, with a related allowance	667,000	0	1,101,000	0
Upaid contractual principal balance	6,880,000		6,880,000		4,028,000
Recorded principal balance	6,599,000		6,599,000		4,007,000
Average recorded principal balance	6,714,000	0	5,354,000	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,697,000		1,697,000		1,586,000
Recorded principal balance, with no related allowance	1,661,000		1,661,000		1,579,000
Average recorded principal balance, with no related allowance	1,596,000	0	1,432,000	0
Unpaid contractual principal balance, with a related allowance	66,000		66,000		0
Recorded principal balance, with a related allowance	66,000		66,000		0
Related allowance	5,000		5,000		0
Average recorded principal balance, with a related allowance	73,000	0	65,000	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	0		0		0
Recorded principal balance, with no related allowance	0		0		0
Average recorded principal balance, with no related allowance	0	0	0	0
Unpaid contractual principal balance, with a related allowance	0		0		0
Recorded principal balance, with a related allowance	0		0		0
Related allowance	0		0		0
Average recorded principal balance, with a related allowance	0	0	0	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,593,000		1,593,000		113,000
Recorded principal balance, with no related allowance	1,391,000		1,391,000		113,000
Average recorded principal balance, with no related allowance	910,000	0	535,000	0
Unpaid contractual principal balance, with a related allowance	51,000		51,000		1,516,000
Recorded principal balance, with a related allowance	51,000		51,000		1,502,000
Related allowance	4,000		4,000		605,000
Average recorded principal balance, with a related allowance	568,000	0	1,016,000	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	768,000		768,000		326,000
Recorded principal balance, with no related allowance	768,000		768,000		326,000
Average recorded principal balance, with no related allowance	656,000	0	487,000	0
Unpaid contractual principal balance, with a related allowance	0		0		0
Recorded principal balance, with a related allowance	0		0		0
Related allowance	0		0		0
Average recorded principal balance, with a related allowance	0	0	0	0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	2,680,000		2,680,000		487,000
Recorded principal balance, with no related allowance	2,637,000		2,637,000		487,000
Average recorded principal balance, with no related allowance	2,885,000	0	1,799,000	0
Unpaid contractual principal balance, with a related allowance	25,000		25,000		0
Recorded principal balance, with a related allowance	25,000		25,000		0
Related allowance	0		0		0
Average recorded principal balance, with a related allowance	26,000	0	20,000	0
Retail Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,613,000		1,613,000		1,351,000
Recorded principal balance, with no related allowance	925,000		925,000		751,000
Average recorded principal balance, with no related allowance	905,000	1,195,000	821,000	1,189,000
Unpaid contractual principal balance, with a related allowance	360,000		360,000		2,309,000
Recorded principal balance, with a related allowance	287,000		287,000		2,084,000
Related allowance	170,000		170,000		778,000
Average recorded principal balance, with a related allowance	291,000	2,181,000	784,000	2,283,000
Upaid contractual principal balance	1,973,000		1,973,000		3,660,000
Recorded principal balance	1,212,000		1,212,000		2,835,000
Average recorded principal balance	1,196,000	3,376,000	1,605,000	3,472,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	214,000		214,000		207,000
Recorded principal balance, with no related allowance	190,000		190,000		191,000
Average recorded principal balance, with no related allowance	189,000	642,000	190,000	598,000
Unpaid contractual principal balance, with a related allowance	195,000		195,000		115,000
Recorded principal balance, with a related allowance	157,000		157,000		84,000
Related allowance	121,000		121,000		84,000
Average recorded principal balance, with a related allowance	160,000	88,000	143,000	139,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,399,000		1,399,000		1,144,000
Recorded principal balance, with no related allowance	735,000		735,000		560,000
Average recorded principal balance, with no related allowance	716,000	553,000	631,000	591,000
Unpaid contractual principal balance, with a related allowance	165,000		165,000		2,194,000
Recorded principal balance, with a related allowance	130,000		130,000		2,000,000
Related allowance	49,000		49,000		694,000
Average recorded principal balance, with a related allowance	131,000	2,093,000	641,000	2,144,000
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,479,000		1,479,000		1,507,000
Recorded principal balance, with no related allowance	1,275,000		1,275,000		1,505,000
Average recorded principal balance, with no related allowance	1,158,000	0	1,278,000	0
Unpaid contractual principal balance, with a related allowance	176,000		176,000		0
Recorded principal balance, with a related allowance	176,000		176,000		0
Related allowance	6,000		6,000		0
Average recorded principal balance, with a related allowance	229,000	0	185,000	0
Upaid contractual principal balance	1,655,000		1,655,000		1,507,000
Recorded principal balance	1,451,000		1,451,000		1,505,000
Average recorded principal balance	1,387,000	0	1,463,000	0
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	449,000		449,000		641,000
Recorded principal balance, with no related allowance	322,000		322,000		639,000
Average recorded principal balance, with no related allowance	342,000	0	423,000	0
Unpaid contractual principal balance, with a related allowance	0		0		0
Recorded principal balance, with a related allowance	0		0		0
Related allowance	0		0		0
Average recorded principal balance, with a related allowance	0	0	0	0
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,030,000		1,030,000		866,000
Recorded principal balance, with no related allowance	953,000		953,000		866,000
Average recorded principal balance, with no related allowance	816,000	0	855,000	0
Unpaid contractual principal balance, with a related allowance	176,000		176,000		0
Recorded principal balance, with a related allowance	176,000		176,000		0
Related allowance	6,000		6,000		$ 0
Average recorded principal balance, with a related allowance	$ 229,000	$ 0	$ 185,000	$ 0

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