Note 6 - Discontinued Operations - Information by Major Classes of Line Items Disclosed as Discontinued Operations in the Consolidated Statements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Pretax loss of discontinued operations related to major classes of pretax profit	$ (848)	$ (973)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax, Total	129,000
Pretax loss on impairment	(130,000)
Income tax benefit
Total loss on discontinued operations that is presented in the Statements of Operations	(848)	(973)
Dillco Fluid Service, Inc [Member]
Accounts receivable, net	97	601
Inventories		67
Property and equipment, net	177	1,105
Receivable from equipment sales	760
Prepaid expenses and other current assets	7	24
Total major classes of assets of the discontinued operation	1,041	1,797
Accounts payable and accrued liabilities	44	189
Total liabilities included as part of discontinued operations	44	189
Revenue	2,433	3,684
Cost of sales	(2,936)	(3,979)
Selling, general, and administrative expenses	(69)	(68)
Depreciation and amortization	(275)	(655)
Other income and expense items that are not major		45
Pretax loss of discontinued operations related to major classes of pretax profit	(847)	(973)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax, Total	129
Pretax loss on impairment	(130)
Income tax benefit
Total loss on discontinued operations that is presented in the Statements of Operations	$ (848)	$ (973)