Note 5 - Loans - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financing Receivables:
Financing receivables, ending balance	$ 4,957,755	$ 4,819,134
Financing receivables, individually evaluated for impairment	54,836	51,983
Financing receivables, collectively evaluated for impairment	4,902,919	4,767,151
Ending balance: individually evaluated for impairment	2,917	3,226
Ending balance: collectively evaluated for impairment	19,294	19,003
Multi-family Residential Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	2,261,946	2,178,504
Financing receivables, individually evaluated for impairment	5,299	5,923
Financing receivables, collectively evaluated for impairment	2,256,647	2,172,581
Ending balance: individually evaluated for impairment	227	232
Ending balance: collectively evaluated for impairment	5,681	5,691
Commercial Real Estate Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	1,268,770	1,246,132
Financing receivables, individually evaluated for impairment	9,409	6,551
Financing receivables, collectively evaluated for impairment	1,259,361	1,239,581
Ending balance: individually evaluated for impairment	168	179
Ending balance: collectively evaluated for impairment	4,317	4,308
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	561,355	558,502
Financing receivables, individually evaluated for impairment	7,311	8,809
Financing receivables, collectively evaluated for impairment	554,044	549,693
Ending balance: individually evaluated for impairment	240	417
Ending balance: collectively evaluated for impairment	2,451	2,486
One-To-Four Family - Residential Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	184,201	185,767
Financing receivables, individually evaluated for impairment	10,566	9,989
Financing receivables, collectively evaluated for impairment	173,635	175,778
Ending balance: individually evaluated for impairment	59	60
Ending balance: collectively evaluated for impairment	920	955
Co-Operative Apartments Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	7,216	7,418
Financing receivables, individually evaluated for impairment	0	0
Financing receivables, collectively evaluated for impairment	7,216	7,418
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	0	0
Construction Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	12,413	11,495
Financing receivables, individually evaluated for impairment	602
Financing receivables, collectively evaluated for impairment	11,811	11,495
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	94	92
Small Business Administration Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	10,519	15,198
Financing receivables, individually evaluated for impairment	170	1,937
Financing receivables, collectively evaluated for impairment	10,349	13,261
Ending balance: individually evaluated for impairment		90
Ending balance: collectively evaluated for impairment	316	391
Taxi Medallion Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	18,832	18,996
Financing receivables, individually evaluated for impairment	18,832	16,282
Financing receivables, collectively evaluated for impairment		2,714
Ending balance: individually evaluated for impairment	2,213	2,236
Ending balance: collectively evaluated for impairment		7
Commercial Business and Other Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	632,503	597,122
Financing receivables, individually evaluated for impairment	2,647	2,492
Financing receivables, collectively evaluated for impairment	629,856	594,630
Ending balance: individually evaluated for impairment	10	12
Ending balance: collectively evaluated for impairment	4,700	4,480
Unallocated Financing Receivables [Member]
Financing Receivables:
Financing receivables, ending balance	0	0
Financing receivables, individually evaluated for impairment	0	0
Financing receivables, collectively evaluated for impairment	0	0
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	$ 815	$ 593

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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-Publisher FASB
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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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