Note 3 - Loans and Allowance for Loan Losses - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Beginning balance	$ 22,229	$ 21,535	$ 25,096
Charge-off's	(12,472)	(1,159)	(3,845)
Recoveries	733	1,853	1,240
Provision (benefit)	9,861		(956)
Ending balance	20,351	22,229	21,535
Multi-family Residential Portfolio Segment [Member]
Beginning balance	5,923	6,718	8,827
Charge-off's	(454)	(161)	(474)
Recoveries	300	339	269
Provision (benefit)	54	(973)	(1,904)
Ending balance	5,823	5,923	6,718
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	4,487	4,239	4,202
Charge-off's	(4)		(32)
Recoveries	96	11	168
Provision (benefit)	64	237	(99)
Ending balance	4,643	4,487	4,239
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Beginning balance	2,903	4,227	5,840
Charge-off's	(39)	(144)	(592)
Recoveries	108	777	76
Provision (benefit)	(427)	(1,957)	(1,097)
Ending balance	2,545	2,903	4,227
One-To-Four Family - Residential Portfolio Segment [Member]
Beginning balance	1,015	1,227	1,690
Charge-off's	(415)	(114)	(342)
Recoveries	91	366	375
Provision (benefit)	391	(464)	(496)
Ending balance	1,082	1,015	1,227
Co-Operative Apartments Portfolio Segment [Member]
Beginning balance	0	0
Charge-off's	0	0	0
Recoveries	0	0
Provision (benefit)	0	0
Ending balance	0	0	0
Construction Portfolio Segment [Member]
Beginning balance	92	50	42
Charge-off's	0	0	0
Recoveries	0	0	0
Provision (benefit)	(24)	42	8
Ending balance	68	92	50
Small Business Administration Portfolio Segment [Member]
Beginning balance	481	262	279
Charge-off's	(212)	(529)	(34)
Recoveries	80	99	40
Provision (benefit)	320	649	(23)
Ending balance	669	481	262
Taxi Medallion Portfolio Segment [Member]
Beginning balance	2,243	343	11
Charge-off's	(11,283)	(142)	0
Recoveries	0	0	0
Provision (benefit)	9,040	2,042	332
Ending balance		2,243	343
Commercial Business and Other Portfolio Segment [Member]
Beginning balance	4,492	4,469	4,205
Charge-off's	(65)	(69)	(2,371)
Recoveries	58	261	312
Provision (benefit)	1,036	(169)	2,323
Ending balance	5,521	4,492	4,469
Unallocated Financing Receivables [Member]
Beginning balance	593
Charge-off's	0
Recoveries	0
Provision (benefit)	(593)	593
Ending balance		$ 593

A valuation allowance for financing receivables that are expected to be uncollectible.

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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 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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