Note 5 - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Mortgage Receivable [Member] \| Multi-family Residential Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	$ 6,108		$ 5,742
Unpaid Principal Balance, With no related allowance recorded	6,818		6,410
Recorded Investment, With an allowance recorded	2,294		2,305
Unpaid Principal Balance, With an allowance recorded	2,294		2,305
Related Allowance	247		252
Average Recorded Investment, With no related allowance recorded	5,925	$ 10,905
Interest Income Recognized, With no related allowance recorded	17	56
Average Recorded Investment, With an allowance recorded	2,300	2,597
Interest Income Recognized, With an allowance recorded	29	32
Mortgage Receivable [Member] \| Commercial Real Estate Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	5,202		3,812
Unpaid Principal Balance, With no related allowance recorded	5,259		3,869
Recorded Investment, With an allowance recorded	2,358		2,371
Unpaid Principal Balance, With an allowance recorded	2,358		2,371
Related Allowance	171		180
Average Recorded Investment, With no related allowance recorded	4,507	6,567
Interest Income Recognized, With no related allowance recorded	12	39
Average Recorded Investment, With an allowance recorded	2,365	1,458
Interest Income Recognized, With an allowance recorded	28	7
Mortgage Receivable [Member] \| One-To-Four Family - Mixed Used Property [Member]
Average Recorded Investment, With no related allowance recorded	9,418	11,749
Interest Income Recognized, With no related allowance recorded	33	57
Average Recorded Investment, With an allowance recorded	2,739	3,085
Interest Income Recognized, With an allowance recorded	38	42
Mortgage Receivable [Member] \| One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	8,754		10,082
Unpaid Principal Balance, With no related allowance recorded	9,698		11,335
Recorded Investment, With an allowance recorded	2,731		2,746
Unpaid Principal Balance, With an allowance recorded	2,731		2,746
Related Allowance	491		502
Mortgage Receivable [Member] \| One-To-Four Family - Residential Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	10,964		12,255
Unpaid Principal Balance, With no related allowance recorded	12,558		14,345
Recorded Investment, With an allowance recorded	341		343
Unpaid Principal Balance, With an allowance recorded	341		343
Related Allowance	50		$ 51
Average Recorded Investment, With no related allowance recorded	11,610	13,210
Interest Income Recognized, With no related allowance recorded	27	25
Average Recorded Investment, With an allowance recorded	342	353
Interest Income Recognized, With an allowance recorded	$ 3	$ 4
Mortgage Receivable [Member] \| Co-Operative Apartments Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded
Unpaid Principal Balance, With no related allowance recorded
Recorded Investment, With an allowance recorded
Unpaid Principal Balance, With an allowance recorded
Related Allowance
Average Recorded Investment, With no related allowance recorded
Interest Income Recognized, With no related allowance recorded
Average Recorded Investment, With an allowance recorded
Interest Income Recognized, With an allowance recorded
Mortgage Receivable [Member] \| Construction Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	$ 570		$ 1,000
Unpaid Principal Balance, With no related allowance recorded	$ 570		$ 1,000
Recorded Investment, With an allowance recorded
Unpaid Principal Balance, With an allowance recorded
Related Allowance
Average Recorded Investment, With no related allowance recorded	$ 785
Interest Income Recognized, With no related allowance recorded
Average Recorded Investment, With an allowance recorded
Interest Income Recognized, With an allowance recorded
Mortgage Receivable [Member]
Related Allowance	$ 959		$ 985
Recorded Investment, Total Impaired Loans	39,322		40,656
Unpaid Principal Balance, Total Impaired Loans	42,627		44,724
Average Recorded Investment, Total Impaired Loans	39,991	$ 49,924
Interest Income Recognized, Total Impaired Loans	187	262
Non-Mortgage Loans [Member] \| Small Business Administration Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	252		276
Unpaid Principal Balance, With no related allowance recorded	252		276
Recorded Investment, With an allowance recorded	150		34
Unpaid Principal Balance, With an allowance recorded	150		$ 34
Related Allowance	47
Average Recorded Investment, With no related allowance recorded	264	159
Interest Income Recognized, With no related allowance recorded	3	1
Average Recorded Investment, With an allowance recorded	92	21
Interest Income Recognized, With an allowance recorded	$ 2	$ 1
Non-Mortgage Loans [Member] \| Taxi Medallion Portflio Segment [Member]
Recorded Investment, With no related allowance recorded
Unpaid Principal Balance, With no related allowance recorded
Recorded Investment, With an allowance recorded	$ 2,110		$ 2,118
Unpaid Principal Balance, With an allowance recorded	2,110		2,118
Related Allowance	$ 325		333
Average Recorded Investment, With no related allowance recorded
Interest Income Recognized, With no related allowance recorded
Average Recorded Investment, With an allowance recorded	$ 2,114
Interest Income Recognized, With an allowance recorded	15
Non-Mortgage Loans [Member] \| Commercial Business and Other Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	2,374		2,682
Unpaid Principal Balance, With no related allowance recorded	2,744		5,347
Recorded Investment, With an allowance recorded	1,992		2,034
Unpaid Principal Balance, With an allowance recorded	1,992		2,034
Related Allowance	108		112
Average Recorded Investment, With no related allowance recorded	2,528	$ 4,511
Interest Income Recognized, With no related allowance recorded	46	69
Average Recorded Investment, With an allowance recorded	2,013	2,660
Interest Income Recognized, With an allowance recorded	25	35
Non-Mortgage Loans [Member]
Related Allowance	480		445
Recorded Investment, Total Impaired Loans	6,878		7,144
Unpaid Principal Balance, Total Impaired Loans	7,248		9,809
Average Recorded Investment, Total Impaired Loans	7,011	7,351
Interest Income Recognized, Total Impaired Loans	91	106
Multi-family Residential Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	14,295		9,782
Commercial Real Estate Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	6,703		5,633
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	12,373		14,077
One-To-Four Family - Residential Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	$ 12,502		$ 13,692
Co-Operative Apartments Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans
Construction Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	$ 570		$ 1,000
Small Business Administration Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	830		453
Taxi Medallion Portflio Segment [Member]
Recorded Investment, Total Impaired Loans	2,110		2,118
Commercial Business and Other Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	2,950		3,123
Recorded Investment, With no related allowance recorded	34,224		35,849
Unpaid Principal Balance, With no related allowance recorded	37,899		42,582
Recorded Investment, With an allowance recorded	11,976		11,951
Unpaid Principal Balance, With an allowance recorded	11,976		11,951
Related Allowance	1,439		1,430
Recorded Investment, Total Impaired Loans	52,333		$ 49,878
Average Recorded Investment, With no related allowance recorded	35,037	47,101
Interest Income Recognized, With no related allowance recorded	138	247
Average Recorded Investment, With an allowance recorded	11,965	10,174
Interest Income Recognized, With an allowance recorded	$ 140	$ 121

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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+ References

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
-SubTopic 10
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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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