Note 5 - Loans - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing receivables, ending balance	$ 5,750,400	$ 5,536,296
Ending balance: collectively evaluated for impairment	5,728,589	5,510,777
Ending balance: collectively evaluated for impairment	21,726	19,785
Multi-family Residential Portfolio Segment [Member]
Financing receivables, ending balance	2,232,305	2,269,048
Ending balance: collectively evaluated for impairment	2,227,110	2,264,548
Ending balance: collectively evaluated for impairment	5,283	5,576
Commercial Real Estate Portfolio Segment [Member]
Financing receivables, ending balance	1,559,581	1,542,547
Ending balance: collectively evaluated for impairment	1,558,632	1,541,112
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	4,364	4,315
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Financing receivables, ending balance	587,100	577,741
Ending balance: collectively evaluated for impairment	584,908	574,643
Ending balance: collectively evaluated for impairment	1,755	1,724
One-To-Four Family - Residential Portfolio Segment [Member]
Financing receivables, ending balance	184,432	190,350
Ending balance: collectively evaluated for impairment	178,591	183,461
Ending balance: collectively evaluated for impairment	697	698
Co-Operative Apartments Portfolio Segment [Member]
Financing receivables, ending balance	9,089	8,498
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	9,089	8,498
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	0	0
Construction Portfolio Segment [Member]
Financing receivables, ending balance	64,234	50,600
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	64,234	50,600
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	418	329
Small Business Administration Portfolio Segment [Member]
Financing receivables, ending balance	13,982	15,210
Ending balance: collectively evaluated for impairment	12,831	13,943
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	357	418
Taxi Medallion Portfolio Segment [Member]
Financing receivables, ending balance	3,513	4,539
Ending balance: collectively evaluated for impairment	0	0
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	0	0
Commercial Business and Other Portfolio Segment [Member]
Financing receivables, ending balance	1,096,164	877,763
Ending balance: collectively evaluated for impairment	1,093,194	873,972
Ending balance: collectively evaluated for impairment	$ 8,852	$ 6,725

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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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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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.

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