Consolidated Statements of Financial Condition (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities held-to-maturity, fair value	$ 62,466	$ 62,112
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	31,530,595	31,530,595
Common stock, shares outstanding (in shares)	28,218,427	28,157,206
Treasury stock, at average cost (in shares)	3,312,168	3,373,389
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, assets pledged	$ 8,942	$ 5,283
Securities held-to-maturity, fair value	9,198	8,114
Securities available for sale, pledged as collateral	238,818	212,038
Securities available for sale, fair value option	672	772
Other Debt Obligations [Member]
Securities held-to-maturity, assets pledged	402	0
Securities held-to-maturity, fair value	53,268	53,998
Securities available for sale, pledged as collateral	0	0
Securities available for sale, fair value option	$ 13,841	$ 13,548

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