Note 13 - Employee Benefit Plans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	12.00%
Defined Contribution Plan Employers Matching Contribution Vesting Period	5 years
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 36,000	$ 39,000
Accrued Bonuses, Current	1,333,000	904,000
President [Member]
Bonus, Maximum Threshold	$ 1,000,000
Bonus Percentage	5.00%
Accrued Bonuses, Current	$ 118,000	$ 232,000
For Employees Contributing 1 Percent of Gross Earnings [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	0.50%
For Employees Contributing 2 to12 Percent of Gross Earnings [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	1.00%