Income Taxes (Principal Components Of Deferred Taxes) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax asset
California NOL carryforward	$ 2,127	$ 1,243
Inventory	(121)	1,727
Federal NOL carryforward	4,373	1,538
Accrued vacation	153	167
Accrued severance	62	120
California alternative minimum tax credit	107	107
Other	409	38
Total deferred tax asset	7,110	4,940
Deferred tax liability
Property and equipment	(6,244)	(6,889)
Intangible assets and goodwill	(1,246)	(1,032)
Other	(97)	(109)
Total deferred tax liability	(7,587)	(8,030)
Net deferred tax liability, non-current	$ (477)	$ (3,090)