Note 5 - Loans - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Allowance for credit losses:
Beginning balance	$ 20,351	$ 22,229
Charge-off's	(85)	(179)
Recoveries	123	161
Provision (benefit)	153
Ending balance	20,542	22,211
Multi-family Residential Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	5,823	5,923
Charge-off's	(53)	(14)
Recoveries	2	30
Provision (benefit)	(22)	(32)
Ending balance	5,750	5,907
Commercial Real Estate Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	4,643	4,487
Charge-off's
Recoveries		68
Provision (benefit)	(41)	(70)
Ending balance	4,602	4,485
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	2,545	2,903
Charge-off's		(34)
Recoveries
Provision (benefit)	(75)	(178)
Ending balance	2,470	2,691
One-To-Four Family - Residential Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	1,082	1,015
Charge-off's	(1)
Recoveries	108
Provision (benefit)	(148)	(36)
Ending balance	1,041	979
Construction Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	68	92
Charge-off's	0	0
Recoveries	0	0
Provision (benefit)	123	2
Ending balance	191	94
Small Business Administration Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	669	481
Charge-off's	(25)	(65)
Recoveries	6	41
Provision (benefit)	25	(140)
Ending balance	675	317
Taxi Medallion Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance		2,243
Charge-off's		(54)
Recoveries
Provision (benefit)		24
Ending balance		2,213
Commercial Business and Other Portfolio Segment [Member]
Allowance for credit losses:
Beginning balance	5,521	4,492
Charge-off's	(6)	(12)
Recoveries	7	22
Provision (benefit)	291	208
Ending balance	$ 5,813	4,710
Unallocated Financing Receivables [Member]
Allowance for credit losses:
Beginning balance		593
Charge-off's
Recoveries
Provision (benefit)		222
Ending balance		$ 815

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Paragraph 11B
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-Name Accounting Standards Codification
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