Note 5 - Low Income Housing Tax Credit Partnerships - Generated Tax Credits and Benefits From Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Generated tax credits	$ 133	$ 125	$ 266	$ 248
Tax benefits from taxable losses	23	30	46	60
Raymond James California Housing Opportunities Fund II [Member]
Generated tax credits	43	43	85	85
Tax benefits from taxable losses	5	7	10	14
WNC Institutional Tax Credit Fun 38 L.P. [Member]
Generated tax credits	21	22	42	44
Tax benefits from taxable losses	3	4	5	8
Merritt Community Capital Corporation Fund XV, L.P. [Member]
Generated tax credits	47	48	95	96
Tax benefits from taxable losses	6	8	12	16
California Affordable Housing Fund [Member]
Generated tax credits	0	1	0	1
Tax benefits from taxable losses	3	6	7	11
Boston Capital [Member]
Generated tax credits	22	11	44	22
Tax benefits from taxable losses	$ 6	$ 5	$ 12	$ 11