Note 1 - Organization and Summary of Significant Accounting Policies - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Balance	$ 75,622	$ 57,182
Balance	81,428	75,622
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	(929)	(523)
Other comprehensive income (loss) before reclassifications	1,019	(402)
Amounts reclassified from accumulated other comprehensive loss	(39)	(4)
Balance	51	(929)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(1,038)	(987)
Other comprehensive income (loss) before reclassifications	63	(51)
Amounts reclassified from accumulated other comprehensive loss
Balance	(975)	(1,038)
AOCI Attributable to Parent [Member]
Balance	(1,967)	(1,510)
Other comprehensive income (loss) before reclassifications	1,082	(453)
Amounts reclassified from accumulated other comprehensive loss	(39)	(4)
Balance	$ (924)	$ (1,967)