Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 80,783	$ 81,502
Serial preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Serial preferred stock, authorized (in shares)	500,000	500,000
Serial preferred stock, 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)	4,286,516	4,292,838
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	$ 7,748	$ 8,159
Other Debt Obligations [Member]
Securities available for sale, amortized cost	$ 73,035	$ 73,343

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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