Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available for sale, amortized cost	$ 116,700	$ 107,528
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)	4,292,303	4,284,840
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	$ 69,826	$ 54,777
Other Debt Obligations [Member]
Securities available for sale, amortized cost	$ 46,874	$ 52,751

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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