Note 7 - Commitments and Contingencies - Minimum Rental Commitments (Details)	Dec. 31, 2018 USD ($)
Operating leases, total	$ 7,435,000
Operating leases, less than 1 year	1,826,000
Operating leases, 1-3 years	3,053,000
Operating leases, 3-5 years	2,556,000
Operating leases, more than 5 years
Inventory purchase commitments, total	2,195
Inventory purchase commitments, less than 1 year	2,072
Inventory purchase commitments, 1-3 years	123
Inventory purchase commitments, 3-5 years
Inventory purchase commitments, more than 5 years