Note 5 - Lease Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016
Lease term			5 years
Fair Value Inputs, Discount Rate			6.00%
Present value of future lease payments			$ 1,754
Fair value of lease equipment			1,678
Present value of future maintenance exenses			$ 76
Sales	$ 27,716	$ 37,193
Increase (Decrease) in Leasing Receivables	(263)	(247)
Property, Plant and Equipment
Proceeds from Lease Payments	307	307
Interest Income, Other	44	60
Increase (Decrease) in Leasing Receivables	$ 263	$ 247