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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	$ 1,472,000		$ 1,472,000		$ 1,509,000
With no related allowance recorded, principal balance	1,472,000		1,472,000		1,501,000
With no related allowance recorded, average recorded principal balance	1,809,000	$ 1,908,000	1,752,000	$ 1,729,000
With related allowance recorded, unpaid principal balance	222,000		222,000		352,000
With related allowance recorded, principal balance	171,000		171,000		305,000
Related allowance	38,000		38,000		165,000
With related allowance recorded, average recorded principal balance	185,000	436,000	227,000	2,816,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	1,000,000		1,000,000		1,528,000
With no related allowance recorded, principal balance	973,000		973,000		1,494,000
With no related allowance recorded, average recorded principal balance	1,327,000	1,596,000	1,395,000	1,432,000
With related allowance recorded, unpaid principal balance	352,000		352,000		383,000
With related allowance recorded, principal balance	331,000		331,000		376,000
Related allowance	98,000		98,000		102,000
With related allowance recorded, average recorded principal balance	343,000	73,000	361,000	65,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	0		0		0
With no related allowance recorded, principal balance	0		0		0
With no related allowance recorded, average recorded principal balance	0	0	0	101,000
With related allowance recorded, unpaid principal balance	1,493,000		1,493,000		2,017,000
With related allowance recorded, principal balance	1,109,000		1,109,000		1,655,000
Related allowance	44,000		44,000		245,000
With related allowance recorded, average recorded principal balance	1,367,000	2,052,000	1,507,000	2,026,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	0		0		0
With no related allowance recorded, principal balance	0		0		0
With no related allowance recorded, average recorded principal balance	0	0	0	0
With related allowance recorded, unpaid principal balance	0		0		0
With related allowance recorded, principal balance	0		0		0
Related allowance	0		0		0
With related allowance recorded, average recorded principal balance	0	0	0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	503,000		503,000		712,000
With no related allowance recorded, principal balance	404,000		404,000		505,000
With no related allowance recorded, average recorded principal balance	327,000	113,000	307,000	1,032,000
With related allowance recorded, unpaid principal balance	5,907,000		5,907,000		5,867,000
With related allowance recorded, principal balance	1,354,000		1,354,000		1,314,000
Related allowance	232,000		232,000		242,000
With related allowance recorded, average recorded principal balance	1,366,000	1,959,000	1,337,000	8,778,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	809,000		809,000		2,233,000
With no related allowance recorded, principal balance	741,000		741,000		1,952,000
With no related allowance recorded, average recorded principal balance	1,021,000	910,000	1,416,000	535,000
With related allowance recorded, unpaid principal balance	49,000		49,000		51,000
With related allowance recorded, principal balance	49,000		49,000		51,000
Related allowance	4,000		4,000		4,000
With related allowance recorded, average recorded principal balance	49,000	568,000	49,000	1,016,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	5,610,000		5,610,000		5,696,000
With no related allowance recorded, principal balance	5,610,000		5,610,000		5,696,000
With no related allowance recorded, average recorded principal balance	5,616,000	5,747,000	5,647,000	3,204,000
With related allowance recorded, unpaid principal balance	4,635,000		4,635,000		4,841,000
With related allowance recorded, principal balance	4,635,000		4,635,000		4,841,000
Related allowance	177,000		177,000		201,000
With related allowance recorded, average recorded principal balance	4,670,000	4,926,000	4,734,000	10,371,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	1,112,000		1,112,000		880,000
With no related allowance recorded, principal balance	1,111,000		1,111,000		880,000
With no related allowance recorded, average recorded principal balance	961,000	656,000	894,000	487,000
With related allowance recorded, unpaid principal balance	0		0		0
With related allowance recorded, principal balance	0		0		0
Related allowance	0		0		0
With related allowance recorded, average recorded principal balance	0	0	0	0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	0		0		0
With no related allowance recorded, principal balance	0		0		0
With no related allowance recorded, average recorded principal balance	0	151,000	0	232,000
With related allowance recorded, unpaid principal balance	953,000		953,000		1,028,000
With related allowance recorded, principal balance	953,000		953,000		1,028,000
Related allowance	263,000		263,000		365,000
With related allowance recorded, average recorded principal balance	966,000	1,179,000	992,000	1,266,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	485,000		485,000		452,000
With no related allowance recorded, principal balance	360,000		360,000		404,000
With no related allowance recorded, average recorded principal balance	327,000	2,885,000	335,000	1,799,000
With related allowance recorded, unpaid principal balance	2,000		2,000		23,000
With related allowance recorded, principal balance	2,000		2,000		23,000
Related allowance	1,000		1,000		0
With related allowance recorded, average recorded principal balance	11,000	26,000	16,000	20,000
Commercial Portfolio Segment [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	7,585,000		7,585,000		7,917,000
With no related allowance recorded, principal balance	7,486,000		7,486,000		7,702,000
With no related allowance recorded, average recorded principal balance	7,752,000	7,919,000	7,706,000	6,298,000
With related allowance recorded, unpaid principal balance	13,210,000		13,210,000		14,105,000
With related allowance recorded, principal balance	8,222,000		8,222,000		9,143,000
Related allowance	754,000		754,000		1,218,000
With related allowance recorded, average recorded principal balance	8,554,000	10,552,000	8,797,000	25,257,000
Total unpaid principal balance	20,795,000		20,795,000		22,022,000
Total principal balance	15,708,000		15,708,000		16,845,000
Total average recorded principal balance	16,306,000	18,471,000	16,503,000	31,555,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	3,406,000		3,406,000		5,093,000
With no related allowance recorded, principal balance	3,185,000		3,185,000		4,730,000
With no related allowance recorded, average recorded principal balance	3,636,000	6,047,000	4,040,000	4,253,000
With related allowance recorded, unpaid principal balance	403,000		403,000		457,000
With related allowance recorded, principal balance	382,000		382,000		450,000
Related allowance	103,000		103,000		106,000
With related allowance recorded, average recorded principal balance	403,000	667,000	426,000	1,101,000
Total unpaid principal balance	3,809,000		3,809,000		5,550,000
Total principal balance	3,567,000		3,567,000		5,180,000
Total average recorded principal balance	4,039,000	6,714,000	4,466,000	5,354,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	122,000		122,000		14,000
With no related allowance recorded, principal balance	116,000		116,000		5,000
With no related allowance recorded, average recorded principal balance	118,000	189,000	63,000	190,000
With related allowance recorded, unpaid principal balance	632,000		632,000		600,000
With related allowance recorded, principal balance	590,000		590,000		562,000
Related allowance	217,000		217,000		209,000
With related allowance recorded, average recorded principal balance	551,000	160,000	534,000	143,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	497,000		497,000		471,000
With no related allowance recorded, principal balance	329,000		329,000		310,000
With no related allowance recorded, average recorded principal balance	347,000	342,000	320,000	423,000
With related allowance recorded, unpaid principal balance	0		0		0
With related allowance recorded, principal balance	0		0		0
Related allowance	0		0		0
With related allowance recorded, average recorded principal balance	0	0	0	0
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	1,191,000		1,191,000		1,328,000
With no related allowance recorded, principal balance	567,000		567,000		657,000
With no related allowance recorded, average recorded principal balance	618,000	716,000	616,000	631,000
With related allowance recorded, unpaid principal balance	205,000		205,000		165,000
With related allowance recorded, principal balance	160,000		160,000		128,000
Related allowance	69,000		69,000		47,000
With related allowance recorded, average recorded principal balance	162,000	131,000	144,000	641,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	1,697,000		1,697,000		1,804,000
With no related allowance recorded, principal balance	1,309,000		1,309,000		1,548,000
With no related allowance recorded, average recorded principal balance	1,307,000	816,000	1,359,000	855,000
With related allowance recorded, unpaid principal balance	173,000		173,000		175,000
With related allowance recorded, principal balance	173,000		173,000		175,000
Related allowance	5,000		5,000		6,000
With related allowance recorded, average recorded principal balance	174,000	229,000	131,000	185,000
Retail Portfolio Segment [Member] | Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	1,313,000		1,313,000		1,342,000
With no related allowance recorded, principal balance	683,000		683,000		662,000
With no related allowance recorded, average recorded principal balance	736,000	905,000	679,000	821,000
With related allowance recorded, unpaid principal balance	837,000		837,000		765,000
With related allowance recorded, principal balance	750,000		750,000		690,000
Related allowance	286,000		286,000		256,000
With related allowance recorded, average recorded principal balance	713,000	291,000	678,000	784,000
Total unpaid principal balance	2,150,000		2,150,000		2,107,000
Total principal balance	1,433,000		1,433,000		1,352,000
Total average recorded principal balance	1,449,000	1,196,000	1,357,000	1,605,000
Retail Portfolio Segment [Member] | Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	2,194,000		2,194,000		2,275,000
With no related allowance recorded, principal balance	1,638,000		1,638,000		1,858,000
With no related allowance recorded, average recorded principal balance	1,654,000	1,158,000	1,679,000	1,278,000
With related allowance recorded, unpaid principal balance	173,000		173,000		175,000
With related allowance recorded, principal balance	173,000		173,000		175,000
Related allowance	5,000		5,000		6,000
With related allowance recorded, average recorded principal balance	174,000	229,000	131,000	185,000
Total unpaid principal balance	2,367,000		2,367,000		2,450,000
Total principal balance	1,811,000		1,811,000		2,033,000
Total average recorded principal balance	1,828,000	1,387,000	1,810,000	1,463,000
Originated Loan [Member]
With no related allowance recorded, unpaid principal balance	8,898,000		8,898,000		9,259,000
With no related allowance recorded, principal balance	8,169,000		8,169,000		8,364,000
With no related allowance recorded, average recorded principal balance	8,488,000	8,824,000	8,385,000	7,119,000
With related allowance recorded, unpaid principal balance	14,047,000		14,047,000		14,870,000
With related allowance recorded, principal balance	8,972,000		8,972,000		9,833,000
Related allowance	1,040,000		1,040,000		1,474,000
With related allowance recorded, average recorded principal balance	9,267,000	10,843,000	9,475,000	26,041,000
Total unpaid principal balance	22,945,000		22,945,000		24,129,000
Total principal balance	17,141,000		17,141,000		18,197,000
Total average recorded principal balance	17,755,000	19,667,000	17,860,000	33,160,000
Acquired Loan [Member]
With no related allowance recorded, unpaid principal balance	5,600,000		5,600,000		7,368,000
With no related allowance recorded, principal balance	4,823,000		4,823,000		6,588,000
With no related allowance recorded, average recorded principal balance	5,290,000	7,205,000	5,719,000	5,531,000
With related allowance recorded, unpaid principal balance	576,000		576,000		632,000
With related allowance recorded, principal balance	555,000		555,000		625,000
Related allowance	108,000		108,000		112,000
With related allowance recorded, average recorded principal balance	577,000	896,000	557,000	1,286,000
Total unpaid principal balance	6,176,000		6,176,000		8,000,000
Total principal balance	5,378,000		5,378,000		$ 7,213,000
Total average recorded principal balance	$ 5,867,000	$ 8,101,000	$ 6,276,000	$ 6,817,000

X

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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