Consolidated Statements of Financial Condition (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Securities held-to-maturity, fair value	$ 28,217	$ 29,699
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)	28,025,081	28,025,081
Treasury stock, at average cost (in shares)	3,505,514	2,942,329
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, fair value	$ 7,221	$ 7,810
Securities held-to-maturity, assets pledged	4,701	0
Securities available for sale, pledged as collateral	106,607	148,505
Securities available for sale, fair value option	1,330	1,590
Other Debt Obligations [Member]
Securities held-to-maturity, fair value	20,996	21,889
Securities available for sale, pledged as collateral	24,575	44,052
Securities available for sale, fair value option	$ 12,610	$ 12,685

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