Note 10 - Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Operating lease right of use asset	$ 81,455
Operating lease liabilities - current	2,503
Operating lease liabilities - noncurrent	78,662
Total liabilities	81,165
Finance leases, liability, current	42
Finance leases, liability, noncurrent	2,717
Total finance lease liabilities	2,759
Property, Plant and Equipment [Member]
Finance leases, assets	2,519
Accumulated Depreciation and Amortization [Member]
Finance leases, assets, depreciation and amortization	(1,390)
Property, Plant and Equipment, Net [Member]
Finance leases, assets	1,129
Current Portion of Long-term Obligations [Member]
Finance leases, liability, current	42
Long-term Obligations, Net of Current Portion [Member]
Finance leases, liability, noncurrent	$ 2,717