Note 10 - Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Operating Lease, Weighted Average Discount Rate, Percent	3.14%	3.14%
Operating Lease, Weighted Average Remaining Lease Term	5 years 7 months 9 days	5 years 7 months 9 days
Operating Lease, Right-of-Use Asset	$ 36,515	$ 36,515	$ 0
Operating Lease, Right-of-use Asset, Accumulated Amortization	4,100	4,100
Operating Lease, Expense	3,400	6,800
Operating Lease, Payments	$ 2,000	$ 4,100