Note 5 - Loans (Detail) - Activity in the allowance for loan losses: (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Allowance for credit losses:
Balance	$ 31,104	$ 30,344	$ 30,344
Balance	31,027	30,618	31,104
Ending balance: individually evaluated for impairment	1,398		1,494
Ending balance: collectively evaluated for impairment	29,629		29,610
Charge-off's	6,282	6,019	21,269
Recoveries	205	293	1,029
Provision	6,000		21,000
Financing Receivables:
Ending balance, Financing Receivables	3,188,702		3,221,375
Ending balance: individually evaluated for impairment	115,563		128,610
Ending balance: collectively evaluated for impairment	3,073,139		3,092,765
Multi-Family Residential [Member]
Allowance for credit losses:
Balance	13,001	11,267	11,267
Balance	12,395		13,001
Ending balance: individually evaluated for impairment	209		183
Ending balance: collectively evaluated for impairment	12,186		12,818
Charge-off's	1,488		6,016
Recoveries	11		144
Provision	871		7,606
Financing Receivables:
Ending balance, Financing Receivables	1,528,353		1,534,438
Ending balance: individually evaluated for impairment	26,094		21,675
Ending balance: collectively evaluated for impairment	1,502,259		1,512,763
Commercial Real Estate Loans [Member]
Allowance for credit losses:
Balance	5,705	5,210	5,210
Balance	5,660		5,705
Ending balance: individually evaluated for impairment	320		359
Ending balance: collectively evaluated for impairment	5,340		5,346
Charge-off's	681		2,746
Recoveries	80		307
Provision	556		2,934
Financing Receivables:
Ending balance, Financing Receivables	507,932		515,438
Ending balance: individually evaluated for impairment	25,545		23,525
Ending balance: collectively evaluated for impairment	482,387		491,913
One-To-Four Family - Mixed-Use Property [Member]
Allowance for credit losses:
Balance	5,960	5,314	5,314
Balance	6,340		5,960
Ending balance: individually evaluated for impairment	592		571
Ending balance: collectively evaluated for impairment	5,748		5,389
Charge-off's	2,606		4,286
Recoveries	53		358
Provision	2,933		4,574
Financing Receivables:
Ending balance, Financing Receivables	615,661		637,353
Ending balance: individually evaluated for impairment	18,762		26,368
Ending balance: collectively evaluated for impairment	596,899		610,985
One-To-Four Family - Residential [Member]
Allowance for credit losses:
Balance	1,999	1,649	1,649
Balance	2,077		1,999
Ending balance: individually evaluated for impairment	60		94
Ending balance: collectively evaluated for impairment	2,017		1,905
Charge-off's	691		1,583
Recoveries	31		29
Provision	738		1,904
Financing Receivables:
Ending balance, Financing Receivables	197,268		198,968
Ending balance: individually evaluated for impairment	15,548		15,702
Ending balance: collectively evaluated for impairment	181,720		183,266
Co-Operative Apartments [Member]
Allowance for credit losses:
Balance	46	80	80
Balance	88		46
Ending balance: collectively evaluated for impairment	88		46
Charge-off's	74		62
Provision	116		28
Financing Receivables:
Ending balance, Financing Receivables	8,221		6,303
Ending balance: individually evaluated for impairment	267		237
Ending balance: collectively evaluated for impairment	7,954		6,066
Construction [Member]
Allowance for credit losses:
Balance	66	668	668
Balance	67		66
Ending balance: individually evaluated for impairment	37		38
Ending balance: collectively evaluated for impairment	30		28
Charge-off's	234		4,591
Provision	235		3,989
Financing Receivables:
Ending balance, Financing Receivables	10,952		14,381
Ending balance: individually evaluated for impairment	10,229		14,232
Ending balance: collectively evaluated for impairment	723		149
Small Business Administration [Member]
Allowance for credit losses:
Balance	505	987	987
Balance	471		505
Ending balance: collectively evaluated for impairment	471		505
Charge-off's	204		324
Recoveries	30		87
Provision	140		(245)
Financing Receivables:
Ending balance, Financing Receivables	8,812		9,496
Ending balance: individually evaluated for impairment	505		850
Ending balance: collectively evaluated for impairment	8,307		8,646
Taxi Medallion [Member]
Allowance for credit losses:
Balance		41	41
Balance	7		7
Ending balance: collectively evaluated for impairment	7		7
Provision			(34)
Financing Receivables:
Ending balance, Financing Receivables	8,777		9,922
Ending balance: collectively evaluated for impairment	8,777		9,922
Commercial Business And Other [Member]
Allowance for credit losses:
Balance	3,815	5,128	5,128
Balance	3,922		3,815
Ending balance: individually evaluated for impairment	180		249
Ending balance: collectively evaluated for impairment	3,742		3,566
Charge-off's	304		1,661
Recoveries			104
Provision	411		244
Financing Receivables:
Ending balance, Financing Receivables	302,726		295,076
Ending balance: individually evaluated for impairment	18,613		26,021
Ending balance: collectively evaluated for impairment	$ 284,113		$ 269,055