Consolidated Statements of Financial Condition (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities held-to-maturity, fair value	$ 30,002	$ 29,874
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)	28,187,184	27,983,637
Treasury stock, at average cost (in shares)	3,343,411	3,546,958
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, assets pledged	$ 5,030	$ 4,796
Securities held-to-maturity, fair value	7,726	7,366
Securities available for sale, pledged as collateral	235,682	152,670
Securities available for sale, fair value option	934	967
Other Debt Obligations [Member]
Securities held-to-maturity, assets pledged	0	0
Securities held-to-maturity, fair value	22,276	22,508
Securities available for sale, pledged as collateral	13,527	28,871
Securities available for sale, fair value option	$ 13,091	$ 12,843

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