Note 3 - Loans (Details) - The Composition of Loans is as Follows (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,798,654	$ 3,423,008
Unearned loan fees and deferred costs, net	11,719	11,170
Total loans	3,810,373	3,434,178
Multi-Family Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,923,460	1,712,039
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	621,569	512,552
One-To-Four Family - Mixed-Use Property [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	573,779	595,751
One-To-Four Family - Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	187,572	193,726
Co-Operative Apartments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	9,835	10,137
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,286	4,247
Small Business Administration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	7,134	7,792
Taxi Medallion [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	22,519	13,123
Commercial Business And Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 447,500	$ 373,641

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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