Note 6 - Leases - Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Operating lease right-of-use asset	$ 35,929	$ 31,624
Operating lease accumulated depreciation	(7,256)	(5,825)
Operating lease right-of-use asset, net	28,673	25,799
Operating lease, other current liabilities	5,843	5,481
Operating lease, operating lease liabilities	22,948	20,418
Total operating lease liabilities	28,791	25,899
Property and equipment, at cost	420,594	416,511
Accumulated depreciation	(264,699)	(260,264)
Finance lease, property and equipment, net	1,483	546
Finance lease, other current liabilities	252	108
Finance lease, other long-term liabilities	1,241	443
Total finance lease liabilities	$ 1,493	$ 551
Operating leases (in years) (Year)	7 years	7 years
Finance leases (in years) (Year)	6 years	6 years
Operating leases	3.76%	3.72%
Finance leases	3.82%	4.01%
Assets Held Under Finance Leases [Member]
Property and equipment, at cost	$ 1,628	$ 613
Accumulated depreciation	$ (145)	$ (67)