BUSINESS SEGMENTS - Reconciling Information Between Reportable Segments and Consolidated Totals (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting [Abstract]
Segment gross profit (loss)	$ 64,037	$ 58,862	$ 193,859	$ 199,058
Operating expenses:
Research and development expenses	1,284	1,816	5,265	5,110
Selling and marketing expenses	4,895	4,248	13,437	13,541
General and administrative expenses	20,174	22,973	57,869	60,536
Other operating income	(3,125)	(6,250)	(10,519)	(6,250)
Impairment of long-lived assets	0	323	0	1,280
Write-off of unsuccessful exploration and storage activities	377	77	1,144	1,456
Operating income	40,432	35,675	126,663	123,385
Interest income	1,626	2,051	4,868	6,494
Interest expense, net	(35,677)	(34,822)	(106,832)	(99,506)
Derivatives and foreign currency transaction gains (losses)	(891)	2,046	6,237	132
Income attributable to sale of tax benefits	14,356	19,760	48,178	53,034
Other non-operating income, net	124	22	422	122
Income from operations before income tax and equity in earnings of investees	$ 19,970	$ 24,732	$ 79,536	$ 83,661