Note 5 - Qualified Affordable Housing Partnership Investments - Generated Tax Credits and Benefits From Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Generated tax credits	$ 114	$ 120	$ 227	$ 239
Tax benefits from taxable losses	25	26	51	52
Raymond James California Housing Opportunities Fund II [Member]
Generated tax credits	43	43	85	85
Tax benefits from taxable losses	7	8	15	15
WNC Institutional Tax Credit Fun 38 L.P. [Member]
Generated tax credits	23	28	46	56
Tax benefits from taxable losses	4	4	8	7
Merritt Community Capital Corporation Fund XV, L.P. [Member]
Generated tax credits	48	48	96	96
Tax benefits from taxable losses	8	8	16	17
California Affordable Housing Fund [Member]
Generated tax credits		1		2
Tax benefits from taxable losses	$ 6	$ 6	$ 12	$ 13