Note 7 - Income Taxes - Income Tax Effects of Temporary Differences That Comprise Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Noncurrent deferred tax assets (liabilities):
Equity method investment	$ 99
Other accrued expenses	32	50
Property, plant and equipment	(1)	(1)
Notes receivable fair value adjustment	578	413
Employee benefits	66	95
AMT credit	247	698
Net operating loss	7,726	7,743
Gross non-current deferred tax assets	8,747	8,998
Less valuation allowance	(8,500)	(8,504)
Net noncurrent deferred tax assets	$ 247	$ 494