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Note 4 - Loans and Allowance for Loan Losses (Details) - Impaired Loans - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	$ 9,259,000	$ 8,255,000
Recorded principal balance, with no related allowance	8,364,000	5,552,000
Average recorded principal balance, with no related allowance	7,370,000	7,381,000
Unpaid contractual principal balance, with a related allowance	14,870,000	42,757,000
Recorded principal balance, with a related allowance	9,833,000	42,304,000
Related allowance	1,474,000	10,152,000
Average recorded principal balance, with a related allowance	22,800,000	32,806,000
Upaid contractual principal balance	24,129,000	51,012,000
Recorded principal balance	18,197,000	47,856,000
Average recorded principal balance	30,170,000	40,187,000
Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	7,368,000	4,019,000
Recorded principal balance, with no related allowance	6,588,000	4,010,000
Average recorded principal balance, with no related allowance	5,741,000	1,761,000
Unpaid contractual principal balance, with a related allowance	632,000	1,516,000
Recorded principal balance, with a related allowance	625,000	1,502,000
Related allowance	112,000	605,000
Average recorded principal balance, with a related allowance	1,156,000	501,000
Upaid contractual principal balance	8,000,000	5,535,000
Recorded principal balance	7,213,000	5,512,000
Average recorded principal balance	6,897,000	2,262,000
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	7,917,000	6,904,000
Recorded principal balance, with no related allowance	7,702,000	4,801,000
Average recorded principal balance, with no related allowance	6,580,000	6,279,000
Unpaid contractual principal balance, with a related allowance	14,105,000	40,448,000
Recorded principal balance, with a related allowance	9,143,000	40,220,000
Related allowance	1,218,000	9,374,000
Average recorded principal balance, with a related allowance	22,035,000	30,563,000
Upaid contractual principal balance	22,022,000	47,352,000
Recorded principal balance	16,845,000	45,021,000
Average recorded principal balance	28,615,000	36,842,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,509,000	1,170,000
Recorded principal balance, with no related allowance	1,501,000	1,164,000
Average recorded principal balance, with no related allowance	1,683,000	652,000
Unpaid contractual principal balance, with a related allowance	352,000	5,299,000
Recorded principal balance, with a related allowance	305,000	5,226,000
Related allowance	165,000	1,578,000
Average recorded principal balance, with a related allowance	2,314,000	2,759,000
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	540,000
Recorded principal balance, with no related allowance	0	209,000
Average recorded principal balance, with no related allowance	81,000	227,000
Unpaid contractual principal balance, with a related allowance	2,017,000	2,000,000
Recorded principal balance, with a related allowance	1,655,000	2,000,000
Related allowance	245,000	151,000
Average recorded principal balance, with a related allowance	1,952,000	3,229,000
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	712,000	3,609,000
Recorded principal balance, with no related allowance	505,000	1,901,000
Average recorded principal balance, with no related allowance	927,000	4,365,000
Unpaid contractual principal balance, with a related allowance	5,867,000	15,745,000
Recorded principal balance, with a related allowance	1,314,000	15,674,000
Related allowance	242,000	2,200,000
Average recorded principal balance, with a related allowance	7,285,000	4,630,000
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	5,696,000	1,210,000
Recorded principal balance, with no related allowance	5,696,000	1,210,000
Average recorded principal balance, with no related allowance	3,703,000	971,000
Unpaid contractual principal balance, with a related allowance	4,841,000	16,033,000
Recorded principal balance, with a related allowance	4,841,000	15,949,000
Related allowance	201,000	4,779,000
Average recorded principal balance, with a related allowance	9,265,000	18,245,000
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	375,000
Recorded principal balance, with no related allowance	0	317,000
Average recorded principal balance, with no related allowance	186,000	64,000
Unpaid contractual principal balance, with a related allowance	1,028,000	1,371,000
Recorded principal balance, with a related allowance	1,028,000	1,371,000
Related allowance	365,000	666,000
Average recorded principal balance, with a related allowance	1,219,000	1,700,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	5,093,000	2,512,000
Recorded principal balance, with no related allowance	4,730,000	2,505,000
Average recorded principal balance, with no related allowance	4,347,000	1,041,000
Unpaid contractual principal balance, with a related allowance	457,000	1,516,000
Recorded principal balance, with a related allowance	450,000	1,502,000
Related allowance	106,000	605,000
Average recorded principal balance, with a related allowance	971,000	501,000
Upaid contractual principal balance	5,550,000	4,028,000
Recorded principal balance	5,180,000	4,007,000
Average recorded principal balance	5,318,000	1,542,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,528,000	1,586,000
Recorded principal balance, with no related allowance	1,494,000	1,579,000
Average recorded principal balance, with no related allowance	1,444,000	563,000
Unpaid contractual principal balance, with a related allowance	383,000	0
Recorded principal balance, with a related allowance	376,000	0
Related allowance	102,000	0
Average recorded principal balance, with a related allowance	127,000	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
Recorded principal balance, with no related allowance	0	0
Average recorded principal balance, with no related allowance	0	0
Unpaid contractual principal balance, with a related allowance	0	0
Recorded principal balance, with a related allowance	0	0
Related allowance	0	0
Average recorded principal balance, with a related allowance	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	2,233,000	113,000
Recorded principal balance, with no related allowance	1,952,000	113,000
Average recorded principal balance, with no related allowance	818,000	52,000
Unpaid contractual principal balance, with a related allowance	51,000	1,516,000
Recorded principal balance, with a related allowance	51,000	1,502,000
Related allowance	4,000	605,000
Average recorded principal balance, with a related allowance	823,000	501,000
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	880,000	326,000
Recorded principal balance, with no related allowance	880,000	326,000
Average recorded principal balance, with no related allowance	565,000	260,000
Unpaid contractual principal balance, with a related allowance	0	0
Recorded principal balance, with a related allowance	0	0
Related allowance	0	0
Average recorded principal balance, with a related allowance	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	452,000	487,000
Recorded principal balance, with no related allowance	404,000	487,000
Average recorded principal balance, with no related allowance	1,520,000	166,000
Unpaid contractual principal balance, with a related allowance	23,000	0
Recorded principal balance, with a related allowance	23,000	0
Related allowance	0	0
Average recorded principal balance, with a related allowance	21,000	0
Retail Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	1,342,000	1,351,000
Recorded principal balance, with no related allowance	662,000	751,000
Average recorded principal balance, with no related allowance	790,000	1,102,000
Unpaid contractual principal balance, with a related allowance	765,000	2,309,000
Recorded principal balance, with a related allowance	690,000	2,084,000
Related allowance	256,000	778,000
Average recorded principal balance, with a related allowance	765,000	2,243,000
Upaid contractual principal balance	2,107,000	3,660,000
Recorded principal balance	1,352,000	2,835,000
Average recorded principal balance	1,555,000	3,345,000
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	14,000	207,000
Recorded principal balance, with no related allowance	5,000	191,000
Average recorded principal balance, with no related allowance	153,000	517,000
Unpaid contractual principal balance, with a related allowance	600,000	115,000
Recorded principal balance, with a related allowance	562,000	84,000
Related allowance	209,000	84,000
Average recorded principal balance, with a related allowance	227,000	128,000
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	1,328,000	1,144,000
Recorded principal balance, with no related allowance	657,000	560,000
Average recorded principal balance, with no related allowance	637,000	585,000
Unpaid contractual principal balance, with a related allowance	165,000	2,194,000
Recorded principal balance, with a related allowance	128,000	2,000,000
Related allowance	47,000	694,000
Average recorded principal balance, with a related allowance	538,000	2,115,000
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid contractual principal balance, with no related allowance	2,275,000	1,507,000
Recorded principal balance, with no related allowance	1,858,000	1,505,000
Average recorded principal balance, with no related allowance	1,394,000	720,000
Unpaid contractual principal balance, with a related allowance	175,000	0
Recorded principal balance, with a related allowance	175,000	0
Related allowance	6,000	0
Average recorded principal balance, with a related allowance	185,000	0
Upaid contractual principal balance	2,450,000	1,507,000
Recorded principal balance	2,033,000	1,505,000
Average recorded principal balance	1,579,000	720,000
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	471,000	641,000
Recorded principal balance, with no related allowance	310,000	639,000
Average recorded principal balance, with no related allowance	400,000	262,000
Unpaid contractual principal balance, with a related allowance	0	0
Recorded principal balance, with a related allowance	0	0
Related allowance	0	0
Average recorded principal balance, with a related allowance	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	1,804,000	866,000
Recorded principal balance, with no related allowance	1,548,000	866,000
Average recorded principal balance, with no related allowance	994,000	458,000
Unpaid contractual principal balance, with a related allowance	175,000	0
Recorded principal balance, with a related allowance	175,000	0
Related allowance	6,000	0
Average recorded principal balance, with a related allowance	$ 185,000	$ 0

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-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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