Note 3 - Loans and Allowance for Loan Losses - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivables:
Financing receivables, ending balance	$ 4,819,134	$ 4,372,611
Financing receivables, individually evaluated for impairment	51,983	47,800
Financing receivables, collectively evaluated for impairment	4,767,151	4,324,811
Ending balance: individually evaluated for impairment	3,226	1,430
Ending balance: collectively evaluated for impairment	19,003	20,105
Multi-family Residential Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	2,178,504	2,055,228
Financing receivables, individually evaluated for impairment	5,923	8,047
Financing receivables, collectively evaluated for impairment	2,172,581	2,047,181
Ending balance: individually evaluated for impairment	232	252
Ending balance: collectively evaluated for impairment	5,691	6,466
Commercial Real Estate Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	1,246,132	1,001,236
Financing receivables, individually evaluated for impairment	6,551	6,183
Financing receivables, collectively evaluated for impairment	1,239,581	995,053
Ending balance: individually evaluated for impairment	179	180
Ending balance: collectively evaluated for impairment	4,308	4,059
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	558,502	573,043
Financing receivables, individually evaluated for impairment	8,809	12,828
Financing receivables, collectively evaluated for impairment	549,693	560,215
Ending balance: individually evaluated for impairment	417	502
Ending balance: collectively evaluated for impairment	2,486	3,725
One-To-Four Family - Residential Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	185,767	187,838
Financing receivables, individually evaluated for impairment	9,989	12,598
Financing receivables, collectively evaluated for impairment	175,778	175,240
Ending balance: individually evaluated for impairment	60	51
Ending balance: collectively evaluated for impairment	955	1,176
Co-Operative Apartments Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	7,418	8,285
Financing receivables, individually evaluated for impairment	0	0
Financing receivables, collectively evaluated for impairment	7,418	8,285
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	11,495	7,284
Financing receivables, individually evaluated for impairment	0	1,000
Financing receivables, collectively evaluated for impairment	11,495	6,284
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	92	50
Small Business Administration Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	15,198	12,194
Financing receivables, individually evaluated for impairment	1,937	310
Financing receivables, collectively evaluated for impairment	13,261	11,884
Ending balance: individually evaluated for impairment	90	0
Ending balance: collectively evaluated for impairment	391	262
Taxi Medallion Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	18,996	20,881
Financing receivables, individually evaluated for impairment	16,282	2,118
Financing receivables, collectively evaluated for impairment	2,714	18,763
Ending balance: individually evaluated for impairment	2,236	333
Ending balance: collectively evaluated for impairment	7	10
Commercial Business and Other Portfolio Segment [Member]
Financing Receivables:
Financing receivables, ending balance	597,122	506,622
Financing receivables, individually evaluated for impairment	2,492	4,716
Financing receivables, collectively evaluated for impairment	594,630	501,906
Ending balance: individually evaluated for impairment	12	112
Ending balance: collectively evaluated for impairment	4,480	4,357
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	$ 593	$ 0

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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=66008989&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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
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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=65884687&loc=d3e4428-111522

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