Note 6 - Property and Equipment - Property, Plant, and Equipment Useful Life (Details) (Parentheticals)	12 Months Ended
	Dec. 31, 2017
Minimum [Member]
Estimated useful life (Year)	3 years
Maximum [Member]
Estimated useful life (Year)	7 years
Machinery and Equipment [Member] | Minimum [Member]
Estimated useful life (Year)	5 years
Machinery and Equipment [Member] | Maximum [Member]
Estimated useful life (Year)	7 years
Furniture and Fixtures [Member] | Minimum [Member]
Estimated useful life (Year)	3 years
Furniture and Fixtures [Member] | Maximum [Member]
Estimated useful life (Year)	5 years
Leasehold Improvements [Member] | Minimum [Member]
Estimated useful life (Year)	5 years
Leasehold Improvements [Member] | Maximum [Member]
Estimated useful life (Year)	7 years