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Note 10 - Stockholders' Equity (Details Textual) - USD ($)			12 Months Ended
	Dec. 09, 2016	Nov. 30, 2006	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 12, 2007
Common Stock, Par or Stated Value Per Share			$ 0.01	$ 0.01
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance			432,930	407,930
Share-based Payment Arrangement, Expense			$ 572,000	$ 940,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			0	0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 48,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 87 days
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense			$ 572,000	$ 940,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			140,000	116,000
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 106,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 76 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 309,000	$ 621,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	7 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
The 2001 Non-qualified Stock Option Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance		300,000
Common Stock, Par or Stated Value Per Share		$ 0.01
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance			22,930	22,930	22,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period
The 2007 Share Incentive Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance						750,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance			345,000	365,000	365,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period
The 2016 Share Incentive Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance	750,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance			65,000	20,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period