Note 4 - Loans Held for Sale - Delinquent and Non-performing Loans Sold During the Period Indicated (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Nonperforming Financial Instruments [Member]
Loans sold	17	26	24
Proceeds	$ 6,216	$ 7,965	$ 9,146
Net (charge-offs) recoveries	(37)	48	134
Net gain (loss)	$ 415	$ 265	$ 112
Performing Financial Instruments [Member]
Loans sold	27	6	6
Proceeds	$ 50,128	$ 3,534	$ 7,265
Net (charge-offs) recoveries
Net gain (loss)	$ 188	$ 319	$ 310
Multi-family Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold	3	9	9
Proceeds	$ 872	$ 2,680	$ 3,540
Net (charge-offs) recoveries		1	134
Net gain (loss)	$ 38	$ 3	$ (1)
Multi-family Residential Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold	12
Proceeds	$ 18,784
Net (charge-offs) recoveries
Net gain (loss)	$ (36)
Commercial Real Estate Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold	5	2	4
Proceeds	$ 1,821	$ 192	$ 2,615
Net (charge-offs) recoveries	(4)
Net gain (loss)	$ 34		$ 13
Commercial Real Estate Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold	7		1
Proceeds	$ 26,283		$ 3,056
Net (charge-offs) recoveries
Net gain (loss)	$ (28)		$ 30
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold	9	15	10
Proceeds	$ 3,523	$ 5,093	$ 2,831
Net (charge-offs) recoveries	(33)	47
Net gain (loss)	$ 343	$ 262	$ 58
One-To-Four Family - Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Loans sold			1
Proceeds			$ 160
Net (charge-offs) recoveries
Net gain (loss)			$ 42
Small Business Administration Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Loans sold	8	6	5
Proceeds	$ 5,061	$ 3,534	$ 4,209
Net (charge-offs) recoveries
Net gain (loss)	$ 252	$ 319	$ 280

The amount of charge-offs (recoveries) of loans held for sale.

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Amount of net recoveries (charge-offs) during the period on delinquent and non-performing loans during the period.

+ References

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Proceeds from the sales of delinquent and non-performing loans sold during the period.

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Delinquent and non-performing loans sold during the period.

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Net gain (loss) on delinquent and non-performing loans during the period.

+ References

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The amount of gain (loss) realized from the sale of loans held for sale.

+ References

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The number of loans sold during the period that were held for sale.

+ References

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The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3337-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3461-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 55
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82926135&loc=d3e60097-112785

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