Note 5 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Mortgage Receivable [Member] \| Multi-family Residential Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	$ 3,546		$ 3,546		$ 5,742
Unpaid Principal Balance, With no related allowance recorded	3,877		3,877		6,410
Recorded Investment, With an allowance recorded	2,274		2,274		2,305
Unpaid Principal Balance, With an allowance recorded	2,274		2,274		2,305
Related Allowance	237		237		252
Average Recorded Investment, With no related allowance recorded	4,639	$ 8,034	5,129	$ 9,470
Interest Income Recognized, With no related allowance recorded	23	14	69	46
Average Recorded Investment, With an allowance recorded	2,279	2,326	2,284	2,461
Interest Income Recognized, With an allowance recorded	29	30	87	89
Mortgage Receivable [Member] \| Commercial Real Estate Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	4,369		4,369		3,812
Unpaid Principal Balance, With no related allowance recorded	4,396		4,396		3,869
Recorded Investment, With an allowance recorded	2,074		2,074		2,371
Unpaid Principal Balance, With an allowance recorded	2,074		2,074		2,371
Related Allowance	190		190		180
Average Recorded Investment, With no related allowance recorded	4,661	4,930	4,841	5,748
Interest Income Recognized, With no related allowance recorded	55	35	162	107
Average Recorded Investment, With an allowance recorded	2,080	538	2,173	998
Interest Income Recognized, With an allowance recorded	24	7	73	22
Mortgage Receivable [Member] \| One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	7,366		7,366		10,082
Unpaid Principal Balance, With no related allowance recorded	8,418		8,418		11,335
Recorded Investment, With an allowance recorded	2,631		2,631		2,746
Unpaid Principal Balance, With an allowance recorded	2,633		2,633		2,746
Related Allowance	449		449		502
Average Recorded Investment, With no related allowance recorded	8,234	9,814	8,407	10,781
Interest Income Recognized, With no related allowance recorded	37	39	119	133
Average Recorded Investment, With an allowance recorded	2,567	3,054	2,622	3,069
Interest Income Recognized, With an allowance recorded	35	42	107	126
Mortgage Receivable [Member] \| One-To-Four Family - Residential Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	10,074		10,074		12,255
Unpaid Principal Balance, With no related allowance recorded	11,591		11,591		14,345
Recorded Investment, With an allowance recorded	433		433		343
Unpaid Principal Balance, With an allowance recorded	433		433		343
Related Allowance	62		62		51
Average Recorded Investment, With no related allowance recorded	10,204	13,040	10,457	13,125
Interest Income Recognized, With no related allowance recorded	19	28	69	101
Average Recorded Investment, With an allowance recorded	435	348	403	350
Interest Income Recognized, With an allowance recorded	4	3	10	10
Mortgage Receivable [Member] \| Co-Operative Apartments Portfolio Segment [Member]
Recorded Investment, With an allowance recorded
Unpaid Principal Balance, With an allowance recorded
Average Recorded Investment, With no related allowance recorded		307		153
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					1,000
Unpaid Principal Balance, With no related allowance recorded					1,000
Recorded Investment, With an allowance recorded
Unpaid Principal Balance, With an allowance recorded
Average Recorded Investment, With no related allowance recorded	285		380
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	938		938		985
Recorded Investment, Total Impaired Loans	32,767		32,767		40,656
Unpaid Principal Balance, Total Impaired Loans	35,696		35,696		44,724
Average Recorded Investment, Total mortgage loans	35,384	42,391	36,696	46,155
Interest Income Recognized, Total mortgage loans	226	198	696	634
Non-Mortgage Loans [Member] \| Small Business Administration Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	546		546		276
Unpaid Principal Balance, With no related allowance recorded	908		908		276
Recorded Investment, With an allowance recorded	118		118		34
Unpaid Principal Balance, With an allowance recorded	118		118		34
Related Allowance	47		47
Average Recorded Investment, With no related allowance recorded	404	301	353	230
Interest Income Recognized, With no related allowance recorded	13	6	38	18
Average Recorded Investment, With an allowance recorded	397	38	315	29
Interest Income Recognized, With an allowance recorded	1	1	4	1
Non-Mortgage Loans [Member] \| Taxi Medallion Portflio Segment [Member]
Recorded Investment, With no related allowance recorded	10,106		10,106
Unpaid Principal Balance, With no related allowance recorded	10,106		10,106
Recorded Investment, With an allowance recorded	6,553		6,553		2,118
Unpaid Principal Balance, With an allowance recorded	6,553		6,553		2,118
Related Allowance	2,330		2,330		333
Average Recorded Investment, With no related allowance recorded	5,053		3,369
Interest Income Recognized, With no related allowance recorded	52		155
Average Recorded Investment, With an allowance recorded	6,459	1,065	5,009	532
Interest Income Recognized, With an allowance recorded	17	16	91	49
Non-Mortgage Loans [Member] \| Commercial Business and Other Portfolio Segment [Member]
Recorded Investment, With no related allowance recorded	2,170		2,170		2,682
Unpaid Principal Balance, With no related allowance recorded	2,549		2,549		5,347
Recorded Investment, With an allowance recorded	438		438		2,034
Unpaid Principal Balance, With an allowance recorded	439		439		2,034
Related Allowance	13		13		112
Average Recorded Investment, With no related allowance recorded	2,211	3,363	2,265	3,937
Interest Income Recognized, With no related allowance recorded	45	51	136	170
Average Recorded Investment, With an allowance recorded	448	3,064	962	2,862
Interest Income Recognized, With an allowance recorded	7	32	20	120
Non-Mortgage Loans [Member]
Related Allowance	2,390		2,390		445
Recorded Investment, Total Impaired Loans	19,931		19,931		7,144
Unpaid Principal Balance, Total Impaired Loans	20,673		20,673		9,809
Average Recorded Investment, Total mortgage loans	14,972	7,831	12,273	7,590
Interest Income Recognized, Total mortgage loans	135	106	444	358
Multi-family Residential Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	10,934		10,934		9,782
Commercial Real Estate Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	7,701		7,701		5,633
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	11,920		11,920		14,077
One-To-Four Family - Residential Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	11,280		11,280		13,692
Co-Operative Apartments Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans
Construction Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans					1,000
Small Business Administration Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	1,309		1,309		453
Taxi Medallion Portflio Segment [Member]
Recorded Investment, Total Impaired Loans	16,659		16,659		2,118
Commercial Business and Other Portfolio Segment [Member]
Recorded Investment, Total Impaired Loans	3,637		3,637		3,123
Recorded Investment, With no related allowance recorded	38,177		38,177		35,849
Unpaid Principal Balance, With no related allowance recorded	41,845		41,845		42,582
Recorded Investment, With an allowance recorded	14,521		14,521		11,951
Unpaid Principal Balance, With an allowance recorded	14,524		14,524		11,951
Related Allowance	3,328		3,328		1,430
Recorded Investment, Total Impaired Loans	63,440		63,440		$ 49,878
Average Recorded Investment, With no related allowance recorded	35,691	39,789	35,201	43,444
Interest Income Recognized, With no related allowance recorded	244	173	748	575
Average Recorded Investment, With an allowance recorded	14,665	10,433	13,768	10,301
Interest Income Recognized, With an allowance recorded	$ 117	$ 131	$ 392	$ 417

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
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-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
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-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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