Note 2 - New Accounting Standards (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total	$ 1,058,000	$ 160,000	$ 1,951,000	$ (348,000)
Cost of Revenue, Total	$ 2,042,000	1,336,000	$ 3,785,000	2,229,000
Accounting Standards Update 2014-09 [Member] | Retained Earnings [Member]
Cumulative Effect on Retained Earnings, Net of Tax, Total		43,000		86,000
Accounting Standards Update 2014-09 [Member] | Restatement Adjustment [Member]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total		53,000		106,000
Cost of Revenue, Total		$ 10,000		$ 20,000