Note 5 - Loans - Non-performing Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Non-accrual loans	$ 15,735	$ 16,253
Total non-performing loans	15,735	16,253
Mortgage Receivable [Member]
Non-accrual loans	11,022	10,861
Non-Mortgage Loans [Member]
Non-accrual loans	4,713	5,392
Multi-family Residential Portfolio Segment [Member] | Mortgage Receivable [Member]
Non-accrual loans	2,009	2,410
Commercial Real Estate Portfolio Segment [Member] | Mortgage Receivable [Member]
Non-accrual loans	1,050	1,379
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member] | Mortgage Receivable [Member]
Non-accrual loans	1,305	928
One-To-Four Family - Residential Portfolio Segment [Member] | Mortgage Receivable [Member]
Non-accrual loans	5,708	6,144
Construction Portfolio Segment [Member] | Mortgage Receivable [Member]
Non-accrual loans	950
Small Business Administration Portfolio Segment [Member] | Non-Mortgage Loans [Member]
Non-accrual loans	1,227	1,267
Taxi Medallion Portfolio Segment [Member] | Non-Mortgage Loans [Member]
Non-accrual loans	1,372	613
Commercial Business and Other Portfolio Segment [Member] | Non-Mortgage Loans [Member]
Non-accrual loans	$ 2,114	$ 3,512