Note 2 - Securities - Summary of Securities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt securities, amortized cost	$ 99,639,000	$ 100,446,000
Debt securities, gross unrealized gains	86,000	159,000
Debt securities, gross unrealized losses	(2,007,000)	(1,255,000)
Debt securities, fair value	97,718,000	99,350,000
US Treasury and Government [Member]
Debt securities, amortized cost	4,532,000	4,541,000
Debt securities, gross unrealized gains
Debt securities, gross unrealized losses	(87,000)	(69,000)
Debt securities, fair value	4,445,000	4,472,000
US Government-sponsored Enterprises Debt Securities [Member]
Debt securities, amortized cost	17,052,000	14,136,000
Debt securities, gross unrealized gains	30,000	2,000
Debt securities, gross unrealized losses	(299,000)	(212,000)
Debt securities, fair value	16,783,000	13,926,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt securities, amortized cost	27,666,000	20,904,000
Debt securities, gross unrealized gains		7,000
Debt securities, gross unrealized losses	(490,000)	(153,000)
Debt securities, fair value	27,176,000	20,758,000
Collateralized Mortgage Obligations [Member]
Debt securities, amortized cost	19,440,000	22,607,000
Debt securities, gross unrealized gains	34,000	25,000
Debt securities, gross unrealized losses	(810,000)	(708,000)
Debt securities, fair value	18,664,000	21,924,000
US States and Political Subdivisions Debt Securities [Member]
Debt securities, amortized cost	22,943,000	29,249
Debt securities, gross unrealized gains	13,000	87,000
Debt securities, gross unrealized losses	(224,000)	(96,000)
Debt securities, fair value	22,732,000	29,240,000
Corporate Debt Securities [Member]
Debt securities, amortized cost	8,006,000	9,009,000
Debt securities, gross unrealized gains	9,000	38,000
Debt securities, gross unrealized losses	(97,000)	(17,000)
Debt securities, fair value	$ 7,918,000	$ 9,030,000