Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Securities available for sale, amortized cost	$ 272,319	$ 287,966
Serial-preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Serial-preferred stock, shares authorized (in shares)	500,000	500,000
Serial-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)	16,000,000	16,000,000
Common stock, shares issued (in shares)	9,128,662	9,128,662
Treasury stock, shares (in shares)	4,647,686	4,564,087
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale, amortized cost	$ 216,621	$ 247,275
Other Debt Obligations [Member]
Securities available for sale, amortized cost	$ 55,698	$ 40,691

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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