Consolidated Statements of Financial Condition (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Securities held-to-maturity, fair value	$ 63,529	$ 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)	34,087,623	31,530,595
Common stock, shares outstanding (in shares)	30,775,854	28,157,206
Treasury stock, at average cost (in shares)	3,311,769	3,373,389
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, assets pledged	$ 5,853	$ 5,283
Securities held-to-maturity, fair value	8,991	8,114
Securities available for sale, pledged as collateral	264,968	212,038
Securities available for sale, fair value option	505	772
Other Debt Obligations [Member]
Securities held-to-maturity, assets pledged	907	0
Securities held-to-maturity, fair value	54,538	53,998
Securities available for sale, pledged as collateral	6,453	0
Securities available for sale, fair value option	$ 13,998	$ 13,548

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