Note 5 - Loans - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing receivables, individually evaluated for impairment	$ 51,731	$ 51,983
Financing receivables, collectively evaluated for impairment	4,976,732	4,767,151
Ending balance: individually evaluated for impairment	3,095	3,226
Ending balance: collectively evaluated for impairment	19,062	19,003
Financing receivables, ending balance	5,028,463	4,819,134
Multi-family Residential Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	5,102	5,923
Financing receivables, collectively evaluated for impairment	2,238,541	2,172,581
Ending balance: individually evaluated for impairment	328	232
Ending balance: collectively evaluated for impairment	5,589	5,691
Financing receivables, ending balance	2,243,643	2,178,504
Commercial Real Estate Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	7,552	6,551
Financing receivables, collectively evaluated for impairment	1,342,082	1,239,581
Ending balance: individually evaluated for impairment	157	179
Ending balance: collectively evaluated for impairment	4,531	4,308
Financing receivables, ending balance	1,349,634	1,246,132
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	6,708	8,809
Financing receivables, collectively evaluated for impairment	550,198	549,693
Ending balance: individually evaluated for impairment	214	417
Ending balance: collectively evaluated for impairment	2,354	2,486
Financing receivables, ending balance	556,906	558,502
One-To-Four Family - Residential Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	10,806	9,989
Financing receivables, collectively evaluated for impairment	170,407	175,778
Ending balance: individually evaluated for impairment	57	60
Ending balance: collectively evaluated for impairment	933	955
Financing receivables, ending balance	181,213	185,767
Co-Operative Apartments Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	0	0
Financing receivables, collectively evaluated for impairment	7,069	7,418
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	0	0
Financing receivables, ending balance	7,069	7,418
Construction Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	602
Financing receivables, collectively evaluated for impairment	16,240	11,495
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	130	92
Financing receivables, ending balance	16,842	11,495
Small Business Administration Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	150	1,937
Financing receivables, collectively evaluated for impairment	10,441	13,261
Ending balance: individually evaluated for impairment		90
Ending balance: collectively evaluated for impairment	306	391
Financing receivables, ending balance	10,591	15,198
Taxi Medallion Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	18,303	16,282
Financing receivables, collectively evaluated for impairment		2,714
Ending balance: individually evaluated for impairment	2,330	2,236
Ending balance: collectively evaluated for impairment		7
Financing receivables, ending balance	18,303	18,996
Commercial Business and Other Portfolio Segment [Member]
Financing receivables, individually evaluated for impairment	2,508	2,492
Financing receivables, collectively evaluated for impairment	641,754	594,630
Ending balance: individually evaluated for impairment	9	12
Ending balance: collectively evaluated for impairment	4,659	4,480
Financing receivables, ending balance	644,262	597,122
Unallocated Financing Receivables [Member]
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	560	593
Financing receivables, ending balance	$ 0	$ 0

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

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.

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

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

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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