Note 2 - Securities (Details Textual)		12 Months Ended
	Oct. 01, 2018 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Equity Securities, FV-NI		$ 19,000	$ 7,000
Equity Securities, FV-NI, Unrealized Gain (Loss), Total		12,000	(10,000)
Equity Securities Sold, Amount			1,300,000
Equity Securities, FV-NI, Realized Gain (Loss), Total			(43,000)
Debt Securities, Available-for-sale, Restricted		$ 22,100,000	$ 20,600,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		78
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions		29
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total		$ 0
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		30
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		23
Collateralized Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		13
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		10
US Treasury and Government [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions		2
Community First [Member]
Equity Securities, FV-NI, Realized Gain (Loss), Total	$ 690,000
Investment Owned, Balance, Shares | shares	18,000