Note 2 - Discontinued Operations (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2015	Mar. 31, 2015	Dec. 31, 2015
Chem Free [Member] | Discontinued Operations, Disposed of by Sale [Member] | Restricted Cash and Cash Equivalents after Working Capital Adjustment [Member]
Restricted Cash and Cash Equivalents, Current	$ 880,000
Chem Free [Member] | Discontinued Operations, Disposed of by Sale [Member]
Disposal Group, Including Discontinued Operation, Consideration		$ 21,600,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax		18,746,000	$ 18,802,000
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation			56,000
Disposal Group, Including Discontinued Operation, Deferred Tax Liabilities			120,000
Increase in Restricted Cash		$ 3,300,000
Restricted Cash and Cash Equivalents, Current			2,200,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax			18,802,000
Restricted Cash and Cash Equivalents, Current			$ 2,200,000
Disposal Group Including Discontinued Operation, Working Capital Adjustment	$ 220,000