Note 5 - Qualified Affordable Housing Partnership Investments - Generated Tax Credits and Benefits From Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Generated tax credits	$ 114	$ 120	$ 342	$ 360
Tax benefits from taxable losses	25	26	75	78
Raymond James California Housing Opportunities Fund II [Member]
Generated tax credits	43	43	128	127
Tax benefits from taxable losses	7	8	22	23
WNC Institutional Tax Credit Fun 38 L.P. [Member]
Generated tax credits	23	28	70	84
Tax benefits from taxable losses	4	4	11	11
Merritt Community Capital Corporation Fund XV, L.P. [Member]
Generated tax credits	48	48	144	145
Tax benefits from taxable losses	8	8	24	25
California Affordable Housing Fund [Member]
Generated tax credits		1		4
Tax benefits from taxable losses	$ 6	$ 6	$ 18	$ 19