Note 9 - Allowance for Loan Losses and Credit Quality Information - Impaired Loans and Related Allowances (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
One to Four Family Porfolio Segment [Member]
Recorded investment, with no related allowance	$ 343,000		$ 343,000		$ 1,251,000
Unpaid principal balance, with no related allowance	343,000		343,000		1,251,000
Recorded investment, with related allowance	1,165,000		1,165,000		952,000
Unpaid principal balance, with related allowance	1,165,000		1,165,000		952,000
Impaired Financing Receivable, Related Allowance	308,000		308,000		223,000
Recorded investment	1,508,000		1,508,000		2,203,000
Unpaid principal balance	1,508,000		1,508,000		2,203,000
Average recorded investment, with no related allowance	519,000	$ 857,000	763,000	$ 823,000
Interest income recognized, with no related allowance	4,000	3,000	6,000	30,000
Average recorded investment, with related allowance	1,122,000	1,148,000	1,065,000	1,136,000
Interest income recognized, with related allowance	3,000	4,000	8,000	8,000
Average recorded investment	1,641,000	2,005,000	1,828,000	1,959,000
Interest income recognized	7,000	7,000	14,000	38,000
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Recorded investment, with no related allowance	42,000		42,000		44,000
Unpaid principal balance, with no related allowance	160,000		160,000		184,000
Recorded investment, with related allowance	0		0		0
Unpaid principal balance, with related allowance	0		0		0
Impaired Financing Receivable, Related Allowance	0		0		0
Recorded investment	42,000		42,000		44,000
Unpaid principal balance	160,000		160,000		184,000
Average recorded investment, with no related allowance	43,000	47,000	43,000	47,000
Interest income recognized, with no related allowance	2,000	7,000	3,000	14,000
Average recorded investment, with related allowance	0	0	0	5,000
Interest income recognized, with related allowance	0	0	0	0
Average recorded investment	43,000	47,000	43,000	52,000
Interest income recognized	2,000	7,000	3,000	14,000
Commercial Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Recorded investment, with no related allowance	26,000		26,000		25,000
Unpaid principal balance, with no related allowance	1,682,000		1,682,000		1,706,000
Recorded investment, with related allowance	1,747,000		1,747,000		2,135,000
Unpaid principal balance, with related allowance	1,747,000		1,747,000		2,135,000
Impaired Financing Receivable, Related Allowance	197,000		197,000		296,000
Recorded investment	1,773,000		1,773,000		2,160,000
Unpaid principal balance	3,429,000		3,429,000		3,841,000
Average recorded investment, with no related allowance	26,000	7,099,000	26,000	7,205,000
Interest income recognized, with no related allowance	25,000	96,000	48,000	191,000
Average recorded investment, with related allowance	2,002,000	1,672,000	2,046,000	1,864,000
Interest income recognized, with related allowance	7,000	10,000	15,000	18,000
Average recorded investment	2,028,000	8,771,000	2,072,000	9,069,000
Interest income recognized	32,000	106,000	63,000	209,000
Commercial Portfolio Segment [Member] \| Commercial Business Other [Member]
Recorded investment, with no related allowance	0		0		0
Unpaid principal balance, with no related allowance	45,000		45,000		79,000
Recorded investment, with related allowance	335,000		335,000		415,000
Unpaid principal balance, with related allowance	887,000		887,000		967,000
Impaired Financing Receivable, Related Allowance	67,000		67,000		120,000
Recorded investment	335,000		335,000		415,000
Unpaid principal balance	932,000		932,000		1,046,000
Average recorded investment, with no related allowance	0	32,000	0	47,000
Interest income recognized, with no related allowance	0	1,000	0	1,000
Average recorded investment, with related allowance	366,000	433,000	382,000	447,000
Interest income recognized, with related allowance	4,000	5,000	7,000	9,000
Average recorded investment	366,000	465,000	382,000	494,000
Interest income recognized	4,000	6,000	7,000	10,000
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, Related Allowance	67,000		67,000		120,000
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance	589,000		589,000		475,000
Unpaid principal balance, with no related allowance	590,000		590,000		476,000
Recorded investment, with related allowance	545,000		545,000		502,000
Unpaid principal balance, with related allowance	562,000		562,000		519,000
Impaired Financing Receivable, Related Allowance	378,000		378,000		370,000
Recorded investment	1,134,000		1,134,000		977,000
Unpaid principal balance	1,152,000		1,152,000		995,000
Average recorded investment, with no related allowance	546,000	291,000	522,000	348,000
Interest income recognized, with no related allowance	2,000	1,000	4,000	2,000
Average recorded investment, with related allowance	542,000	443,000	529,000	410,000
Interest income recognized, with related allowance	4,000	9,000	6,000	13,000
Average recorded investment	1,088,000	734,000	1,051,000	758,000
Interest income recognized	6,000	10,000	10,000	15,000
Impaired Financing Receivable, Related Allowance	950,000		950,000		1,009,000
Recorded investment	4,792,000		4,792,000		5,799,000
Unpaid principal balance	7,181,000		7,181,000		$ 8,269,000
Average recorded investment	5,166,000	12,022,000	5,376,000	12,332,000
Interest income recognized	$ 51,000	$ 136,000	$ 97,000	$ 286,000

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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+ References

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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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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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 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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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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