Note 13 - Leases (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019
Operating Lease, Weighted Average Remaining Lease Term	37 months	29 months
Operating Lease, Weighted Average Discount Rate, Percent	2.40%	2.10%
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 533,000
Operating Lease, Payments	579,000
Other Operating Income (Expense) [Member]
Operating Lease, Cost	1,900,000
Short-term Lease, Cost	$ 1,300,000
Minimum [Member]
Lessee, Operating Lease, Renewal Term	6 months
Maximum [Member]
Lessee, Operating Lease, Renewal Term	3 years