Note 5 - Loans (Details) - Activity in the Allowance for Loan Losses (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Allowance for credit losses:
Allowance for credit losses - balance	$ 25,096	$ 31,776
Allowance for credit losses - balance	24,091	30,270
Ending balance: individually evaluated for impairment	1,045	1,415
Ending balance: collectively evaluated for impairment	23,046	28,855
Charge-off's	(397)	(901)
Recoveries	126	514
Provision	(734)	(1,119)
Financing Receivables:
Ending Balance	3,984,780	3,488,579	3,798,654
Ending balance: individually evaluated for impairment	58,027	81,928
Ending balance: collectively evaluated for impairment	3,926,753	3,406,651
Multi-Family Residential [Member]
Allowance for credit losses:
Allowance for credit losses - balance	8,827	12,084
Allowance for credit losses - balance	8,629	11,103
Ending balance: individually evaluated for impairment	267	304
Ending balance: collectively evaluated for impairment	8,362	10,799
Charge-off's	(97)	(605)
Recoveries	23	7
Provision	(124)	(383)
Financing Receivables:
Ending Balance	2,013,249	1,722,764	1,923,460
Ending balance: individually evaluated for impairment	13,743	20,898
Ending balance: collectively evaluated for impairment	1,999,506	1,701,866
Commercial Real Estate Loans [Member]
Allowance for credit losses:
Allowance for credit losses - balance	4,202	4,959
Allowance for credit losses - balance	3,902	5,379
Ending balance: individually evaluated for impairment	19	210
Ending balance: collectively evaluated for impairment	3,883	5,169
Charge-off's	(18)	(47)
Recoveries	72	382
Provision	(354)	85
Financing Receivables:
Ending Balance	687,823	509,728	621,569
Ending balance: individually evaluated for impairment	6,575	19,558
Ending balance: collectively evaluated for impairment	681,248	490,170
One-To-Four Family - Mixed-Use Property [Member]
Allowance for credit losses:
Allowance for credit losses - balance	5,840	6,328
Allowance for credit losses - balance	5,429	7,142
Ending balance: individually evaluated for impairment	566	617
Ending balance: collectively evaluated for impairment	4,863	6,525
Charge-off's	(78)	(83)
Recoveries	3	40
Provision	(336)	857
Financing Receivables:
Ending Balance	573,927	587,482	573,779
Ending balance: individually evaluated for impairment	14,548	16,060
Ending balance: collectively evaluated for impairment	559,379	571,422
One-To-Four Family - Residential [Member]
Allowance for credit losses:
Allowance for credit losses - balance	1,690	2,079
Allowance for credit losses - balance	1,465	1,944
Ending balance: individually evaluated for impairment	54	57
Ending balance: collectively evaluated for impairment	1,411	1,887
Charge-off's	(153)	(42)
Recoveries		68
Provision	(72)	(161)
Financing Receivables:
Ending Balance	190,366	194,611	187,572
Ending balance: individually evaluated for impairment	13,954	13,941
Ending balance: collectively evaluated for impairment	176,412	180,670
Co-Operative Apartments [Member]
Allowance for credit losses:
Allowance for credit losses - balance		104
Recoveries		7
Provision		(111)
Financing Receivables:
Ending Balance	9,413	9,974	9,835
Ending balance: collectively evaluated for impairment	9,413	9,974
Construction [Member]
Allowance for credit losses:
Allowance for credit losses - balance	42	444
Allowance for credit losses - balance	23	40
Ending balance: individually evaluated for impairment		9
Ending balance: collectively evaluated for impairment	23	31
Provision	(19)	(404)
Financing Receivables:
Ending Balance	2,828	4,859	5,286
Ending balance: individually evaluated for impairment		1,316
Ending balance: collectively evaluated for impairment	2,828	3,543
Small Business Administration [Member]
Allowance for credit losses:
Allowance for credit losses - balance	279	458
Allowance for credit losses - balance	266	391
Ending balance: collectively evaluated for impairment	266	391
Recoveries	20	10
Provision	(33)	(77)
Financing Receivables:
Ending Balance	8,005	7,628	7,134
Ending balance: individually evaluated for impairment	359
Ending balance: collectively evaluated for impairment	7,646	7,628
Taxi Medallion [Member]
Allowance for credit losses:
Allowance for credit losses - balance			11
Allowance for credit losses - balance	11	14	11
Ending balance: collectively evaluated for impairment	11	14
Provision		14
Financing Receivables:
Ending Balance	21,346	24,127	22,519
Ending balance: collectively evaluated for impairment	21,346	24,127
Commercial Business And Other [Member]
Allowance for credit losses:
Allowance for credit losses - balance	4,205	5,320
Allowance for credit losses - balance	4,366	4,257
Ending balance: individually evaluated for impairment	139	218
Ending balance: collectively evaluated for impairment	4,227	4,039
Charge-off's	(51)	(124)
Recoveries	8
Provision	204	(939)
Financing Receivables:
Ending Balance	477,823	427,406	447,500
Ending balance: individually evaluated for impairment	8,848	10,155
Ending balance: collectively evaluated for impairment	$ 468,975	$ 417,251

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A valuation allowance for financing receivables that are expected to be uncollectible.

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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 of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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