12. Employee Benefits (Details - Fair Value of Plan Assets) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair value of plan assets	$ 16,243	$ 16,374
Company Common Stock [Member]
Fair value of plan assets	4,581	4,643
Large Cap Value [Member]
Fair value of plan assets	2,238	2,061
Mid Cap Index [Member]
Fair value of plan assets	625	578
Small Cap Growth [Member]
Fair value of plan assets	621	552
Small Cap Value [Member]
Fair value of plan assets	687	573
Focus Value [Member]
Fair value of plan assets	676	571
Growth [Member]
Fair value of plan assets	1,980	2,215
International Growth [Member]
Fair value of plan assets	2,392	2,475
Core Bond [Member]
Fair value of plan assets	1,644	1,833
High Yield [Member]
Fair value of plan assets	356	354
Inflation Protected Bond [Member]
Fair value of plan assets	433	482
Money Market [Member]
Fair value of plan assets	10	37
Level 1 [Member]
Fair value of plan assets	4,581	4,643
Level 1 [Member] | Company Common Stock [Member]
Fair value of plan assets	4,581	4,643
Level 1 [Member] | Large Cap Value [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Mid Cap Index [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Small Cap Growth [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Small Cap Value [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Focus Value [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Growth [Member]
Fair value of plan assets	0	0
Level 1 [Member] | International Growth [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Core Bond [Member]
Fair value of plan assets	0	0
Level 1 [Member] | High Yield [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Inflation Protected Bond [Member]
Fair value of plan assets	0	0
Level 1 [Member] | Money Market [Member]
Fair value of plan assets	0	0
Level 2 [Member]
Fair value of plan assets	11,662	11,731
Level 2 [Member] | Company Common Stock [Member]
Fair value of plan assets	0	0
Level 2 [Member] | Large Cap Value [Member]
Fair value of plan assets	2,238	2,061
Level 2 [Member] | Mid Cap Index [Member]
Fair value of plan assets	625	578
Level 2 [Member] | Small Cap Growth [Member]
Fair value of plan assets	621	552
Level 2 [Member] | Small Cap Value [Member]
Fair value of plan assets	687	573
Level 2 [Member] | Focus Value [Member]
Fair value of plan assets	676	571
Level 2 [Member] | Growth [Member]
Fair value of plan assets	1,980	2,215
Level 2 [Member] | International Growth [Member]
Fair value of plan assets	2,392	2,475
Level 2 [Member] | Core Bond [Member]
Fair value of plan assets	1,644	1,833
Level 2 [Member] | High Yield [Member]
Fair value of plan assets	356	354
Level 2 [Member] | Inflation Protected Bond [Member]
Fair value of plan assets	433	482
Level 2 [Member] | Money Market [Member]
Fair value of plan assets	10	37
Level 3 [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Company Common Stock [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Large Cap Value [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Mid Cap Index [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Small Cap Growth [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Small Cap Value [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Focus Value [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Growth [Member]
Fair value of plan assets	0	0
Level 3 [Member] | International Growth [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Core Bond [Member]
Fair value of plan assets	0	0
Level 3 [Member] | High Yield [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Inflation Protected Bond [Member]
Fair value of plan assets	0	0
Level 3 [Member] | Money Market [Member]
Fair value of plan assets	$ 0	$ 0