Note 2 - Securities - Maturity of Securities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Due in one year or less, amortized cost	$ 1,924,000
Due in one year or less, fair value	1,918,000
Due after one year through five years, amortized cost	31,969,000
Due after one year through five years, fair value	31,517,000
Due after five through ten years, amortized cost	15,893,000
Due after five through ten years, fair value	15,747,000
Due after ten years, amortized cost	2,747,000
Due after ten years, fair value	2,696,000
Securities, amortized cost	99,639,000	$ 100,446,000
Securities, fair value	97,718,000	99,350,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities without maturity date, amortized cost	27,666,000
Securities without maturity date, fair value	27,176,000
Securities, amortized cost	27,666,000	20,904,000
Securities, fair value	27,176,000	20,758,000
Collateralized Mortgage Obligations [Member]
Securities without maturity date, amortized cost	19,440,000
Securities without maturity date, fair value	18,664,000
Securities, amortized cost	19,440,000	22,607,000
Securities, fair value	$ 18,664,000	$ 21,924,000

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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