Note 7 - Other Non-current Assets (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Other Assets, Noncurrent [Table Text Block]

Other non-current assets consisted of the following (in thousands):	December 31,		December 31,
	2021		2020
Permitting costs(1)	$	7,609	$	7,385
Enterprise resource planning system, net		389		1,805
Rio Grande Site Lease initial direct costs		13,314		7,109
Total other non-current assets, net	$	21,312	$	16,299