Consolidated Condensed Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands		Mar. 31, 2018	Dec. 31, 2017
Held-to-maturity, fair value (in dollars)	[1]	$ 642	$ 649
Loans receivable, allowance (in dollars)		$ 27,267	$ 26,683
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized		25,000,000	25,000,000
Common Stock, Shares Issued		12,703,320	12,712,841
Common stock, shares outstanding		10,181,899	10,156,041
Accumulated other comprehensive income, tax effect (in dollars)		$ (677)	$ 117
Treasury stock, shares		2,521,421	2,556,800
Preferred Stock [Member]
Preferred stock, par value (in dollars per share)		$ 0.01	$ 0.01
Preferred stock, shares authorized		4,963,000	4,963,000
Preferred stock, shares issued		0	0
Cumulative Preferred Stock [Member]
Preferred stock, par value (in dollars per share)		$ 0.01	$ 0.01
Preferred stock, shares authorized		37,000	37,000
Preferred stock, shares issued		0	0

[1] FHLMC, FNMA, and GNMA certificates are residential mortgage-backed securities.