Note 9 - Allowance for Loan Losses and Credit Quality Information - Impaired Loans and Related Allowances (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
One to Four Family Porfolio Segment [Member]
Recorded investment, with no related allowance	$ 328,000		$ 328,000		$ 1,251,000
Unpaid principal balance, with no related allowance	328,000		328,000		1,251,000
Recorded investment, with related allowance	1,023,000		1,023,000		952,000
Unpaid principal balance, with related allowance	1,023,000		1,023,000		952,000
Impaired Financing Receivable, Related Allowance	242,000		242,000		223,000
Recorded investment	1,351,000		1,351,000		2,203,000
Unpaid principal balance	1,351,000		1,351,000		2,203,000
Average recorded investment, with no related allowance	336,000	$ 989,000	654,000	$ 866,000
Interest income recognized, with no related allowance	5,000	1,000	12,000	32,000
Average recorded investment, with related allowance	1,094,000	968,000	1,055,000	1,069,000
Interest income recognized, with related allowance	5,000	3,000	14,000	10,000
Average recorded investment	1,430,000	1,957,000	1,709,000	1,935,000
Interest income recognized	10,000	4,000	26,000	42,000
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no related allowance	50,000		50,000		44,000
Unpaid principal balance, with no related allowance	127,000		127,000		184,000
Impaired Financing Receivable, Related Allowance	0		0		0
Recorded investment	50		50		44
Unpaid principal balance	127		127		184
Average recorded investment, with no related allowance	46,000	46,000	45,000	47,000
Interest income recognized, with no related allowance	1,000	2,000	4,000	5,000
Average recorded investment, with related allowance		0		4,000
Interest income recognized, with related allowance		0		0
Average recorded investment	46,000	46,000	45,000	51,000
Interest income recognized	1,000	2,000	4,000	5,000
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Recorded investment, with no related allowance	25,000		25,000		25,000
Unpaid principal balance, with no related allowance	1,681,000		1,681,000		1,706,000
Impaired Financing Receivable, Related Allowance	414,000		414,000		296,000
Recorded investment	3,300,000		3,300,000		2,160,000
Unpaid principal balance	5,054,000		5,054,000		3,841,000
Average recorded investment, with no related allowance	26,000	6,338,000	26,000	6,821,000
Interest income recognized, with no related allowance	24,000	103,000	73,000	304,000
Average recorded investment, with related allowance	2,511,000	1,896,000	2,354,000	1,866,000
Interest income recognized, with related allowance	54,000	6,000	183,000	24,000
Average recorded investment	2,537,000	8,234,000	2,380,000	8,687,000
Interest income recognized	78,000	109,000	256,000	328,000
Commercial Real Estate Portfolio Segment [Member]
Impaired Financing Receivable, Related Allowance	414,000		414,000		296,000
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance	367,000		367,000		475,000
Unpaid principal balance, with no related allowance	367,000		367,000		476,000
Recorded investment, with related allowance	549,000		549,000		502,000
Unpaid principal balance, with related allowance	566,000		566,000		519,000
Impaired Financing Receivable, Related Allowance	416,000		416,000		370,000
Recorded investment	916,000		916,000		977,000
Unpaid principal balance	933,000		933,000		995,000
Average recorded investment, with no related allowance	478,000	363,000	483,000	365,000
Interest income recognized, with no related allowance	1,000	1,000	3,000	5,000
Average recorded investment, with related allowance	547,000	531,000	534,000	434,000
Interest income recognized, with related allowance	2,000	2,000	8,000	16,000
Average recorded investment	1,025,000	894,000	1,017,000	799,000
Interest income recognized	3,000	3,000	11,000	21,000
Commercial Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Recorded investment, with related allowance	3,275,000		3,275,000		2,135,000
Unpaid principal balance, with related allowance	3,373,000		3,373,000		2,135,000
Impaired Financing Receivable, Related Allowance	414,000		414,000		296,000
Commercial Portfolio Segment [Member] \| Commercial Business Other [Member]
Recorded investment, with no related allowance	131,000		131,000		0
Unpaid principal balance, with no related allowance	154,000		154,000		79,000
Recorded investment, with related allowance	599,000		599,000		415,000
Unpaid principal balance, with related allowance	1,151,000		1,151,000		967,000
Impaired Financing Receivable, Related Allowance	184,000		184,000		120,000
Recorded investment	730,000		730,000		415,000
Unpaid principal balance	1,305,000		1,305,000		1,046,000
Average recorded investment, with no related allowance	66,000	23,000	33,000	46,000
Interest income recognized, with no related allowance	0	0	0	1,000
Average recorded investment, with related allowance	467,000	397,000	437,000	432,000
Interest income recognized, with related allowance	16,000	4,000	62,000	13,000
Average recorded investment	533,000	420,000	470,000	478,000
Interest income recognized	16,000	4,000	62,000	14,000
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, Related Allowance	184,000		184,000		120,000
Impaired Financing Receivable, Related Allowance	1,256,000		1,256,000		1,009,000
Recorded investment	6,347,000		6,347,000		5,799,000
Unpaid principal balance	8,770,000		8,770,000		$ 8,269,000
Average recorded investment	5,571,000	11,551,000	5,621,000	11,950,000
Interest income recognized	$ 108,000	$ 122,000	$ 359,000	$ 410,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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