Note 2 - New Accounting Standards (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total	$ 893,000	$ (508,000)
Cost of Revenue, Total	$ 1,743,000	893,000
Accounting Standards Update 2014-09 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption		43,000
Accounting Standards Update 2014-09 [Member] | Restatement Adjustment [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total		53,000
Cost of Revenue, Total		$ 10,000