Note 3 - Loans (Details) - Activity in the Allowance for Loan Losses (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for credit losses:
Allowance for credit losses - balance	$ 31,776	$ 31,104	$ 30,344
Allowance for credit losses - balance	25,096	31,776	31,104
Ending balance: individually evaluated for impairment	1,094	1,648
Ending balance: collectively evaluated for impairment	24,002	30,128
Charge-off's	(2,442)	(14,843)	(21,269)
Recoveries	1,783	1,580	1,029
Provision	(6,021)	13,935
Financing Receivables:
Ending balance	3,798,654	3,423,008
Ending balance: individually evaluated for impairment	56,515	81,768
Ending balance: collectively evaluated for impairment	3,742,139	3,341,240
Multi-Family Residential [Member]
Allowance for credit losses:
Allowance for credit losses - balance	12,084	13,001
Allowance for credit losses - balance	8,827	12,084
Ending balance: individually evaluated for impairment	286	312
Ending balance: collectively evaluated for impairment	8,541	11,772
Charge-off's	(1,161)	(3,585)
Recoveries	150	541
Provision	(2,246)	2,127
Financing Receivables:
Ending balance	1,923,460	1,712,039
Ending balance: individually evaluated for impairment	13,260	21,757
Ending balance: collectively evaluated for impairment	1,910,200	1,690,282
Commercial Real Estate Loans [Member]
Allowance for credit losses:
Allowance for credit losses - balance	4,959	5,705
Allowance for credit losses - balance	4,202	4,959
Ending balance: individually evaluated for impairment	21	164
Ending balance: collectively evaluated for impairment	4,181	4,795
Charge-off's	(325)	(1,051)
Recoveries	481	324
Provision	(913)	(19)
Financing Receivables:
Ending balance	621,569	512,552
Ending balance: individually evaluated for impairment	9,473	19,757
Ending balance: collectively evaluated for impairment	612,096	492,795
One-To-Four Family - Mixed-Use Property [Member]
Allowance for credit losses:
Allowance for credit losses - balance	6,328	5,960
Allowance for credit losses - balance	5,840	6,328
Ending balance: individually evaluated for impairment	579	875
Ending balance: collectively evaluated for impairment	5,261	5,453
Charge-off's	(423)	(4,206)
Recoveries	608	266
Provision	(673)	4,308
Financing Receivables:
Ending balance	573,779	595,751
Ending balance: individually evaluated for impairment	15,120	16,939
Ending balance: collectively evaluated for impairment	558,659	578,812
One-To-Four Family - Residential [Member]
Allowance for credit losses:
Allowance for credit losses - balance	2,079	1,999
Allowance for credit losses - balance	1,690	2,079
Ending balance: individually evaluated for impairment	54	58
Ending balance: collectively evaluated for impairment	1,636	2,021
Charge-off's	(103)	(701)
Recoveries	269	272
Provision	(555)	509
Financing Receivables:
Ending balance	187,572	193,726
Ending balance: individually evaluated for impairment	13,170	14,390
Ending balance: collectively evaluated for impairment	174,402	179,336
Co-Operative Apartments [Member]
Allowance for credit losses:
Allowance for credit losses - balance	104	46
Allowance for credit losses - balance		104
Ending balance: collectively evaluated for impairment		104
Charge-off's		(108)
Recoveries	7	4
Provision	(111)	162
Financing Receivables:
Ending balance	9,835	10,137
Ending balance: individually evaluated for impairment		59
Ending balance: collectively evaluated for impairment	9,835	10,078
Construction [Member]
Allowance for credit losses:
Allowance for credit losses - balance	444	66
Allowance for credit losses - balance	42	444
Ending balance: individually evaluated for impairment		17
Ending balance: collectively evaluated for impairment	42	427
Charge-off's		(2,678)
Provision	(402)	3,056
Financing Receivables:
Ending balance	5,286	4,247
Ending balance: individually evaluated for impairment		746
Ending balance: collectively evaluated for impairment	5,286	3,501
Small Business Administration [Member]
Allowance for credit losses:
Allowance for credit losses - balance	458	505
Allowance for credit losses - balance	279	458
Ending balance: collectively evaluated for impairment	279	458
Charge-off's	(49)	(457)
Recoveries	92	87
Provision	(222)	323
Financing Receivables:
Ending balance	7,134	7,792
Ending balance: collectively evaluated for impairment	7,134	7,792
Taxi Medallion [Member]
Allowance for credit losses:
Allowance for credit losses - balance		7
Allowance for credit losses - balance	11
Ending balance: collectively evaluated for impairment	11
Provision	11	(7)
Financing Receivables:
Ending balance	22,519	13,123
Ending balance: collectively evaluated for impairment	22,519	13,123
Commercial Business And Other [Member]
Allowance for credit losses:
Allowance for credit losses - balance	5,320	3,815
Allowance for credit losses - balance	4,205	5,320
Ending balance: individually evaluated for impairment	154	222
Ending balance: collectively evaluated for impairment	4,051	5,098
Charge-off's	(381)	(2,057)
Recoveries	176	86
Provision	(910)	3,476
Financing Receivables:
Ending balance	447,500	373,641
Ending balance: individually evaluated for impairment	5,492	8,120
Ending balance: collectively evaluated for impairment	$ 442,008	$ 365,521