Note 3 - Summary of Significant Accounting Policies - Quantitative Information About Level 3 Fair Value Measurements (Details) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2018	Dec. 31, 2017
Valuation, Income Approach [Member] | Measurement Input, Expected Term [Member]
Intangible assets	0.0775
Valuation, Income Approach [Member] | Measurement Input, Discount Rate [Member]
Intangible assets	0.24	0.24
Valuation, Income Approach [Member] | Measurement Input, Terminal Growth Rate [Member]
Goodwill	3.5
Goodwill	3.5
Valuation, Income Approach [Member] | Measurement Input, Terminal Growth Rate [Member] | Minimum [Member]
Goodwill
Goodwill
Valuation, Income Approach [Member] | Measurement Input, Terminal Growth Rate [Member] | Maximum [Member]
Goodwill
Goodwill
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Expected Term [Member]
Goodwill	0.05	5
Goodwill	0.05	5
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Expected Term [Member] | Minimum [Member]
Intangible assets		3.25
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Expected Term [Member] | Maximum [Member]
Intangible assets		8.5
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Discount Rate [Member]
Goodwill	0.2	0.2
Goodwill	0.2	0.2
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Contributory Asset Charge [Member] | Minimum [Member]
Intangible assets	8.9	0.159
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Contributory Asset Charge [Member] | Maximum [Member]
Intangible assets	24	0.24
Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Terminal Growth Rate [Member]
Goodwill		3.5
Goodwill		3.5