Note 6 - Other Non-current Assets - Schedule of Other Non-current Assets (Details) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Permitting costs	[1]	$ 7,409	$ 7,385
Enterprise resource planning system, net		743	1,805
Rio Grande Site Lease initial direct costs		11,751	7,109
Total other non-current assets, net		$ 19,903	$ 16,299

[1] Permitting costs primarily represent costs incurred in connection with permit applications to the United States Army Corps of Engineers and the U.S. Fish and Wildlife Service for mitigation measures for potential impacts to wetlands and habitat that may be caused by the construction of the Terminal and the Pipeline.