EARNINGS PER LIMITED PARTNER UNIT (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
EARNINGS PER LIMITED PARTNER UNIT
Net Income (Loss)	$ 360,855	$ 630,118	$ 586,200
General partner's interest in net income attributable to ARLP		(1,384)	(9,010)
Limited partners' interest in net income attributable to ARLP	360,855	628,734	577,190
Distributions to participating securities	(6,005)	(9,688)	(8,527)
Undistributed earnings attributable to participating securities		(7,203)	(10,576)
Net income attributable to ARLP available to limited partners	$ 354,850	$ 611,843	$ 558,087
Weighted-average limited partner units outstanding - basic (in units)	127,964,744	127,180,312	127,195,219
Weighted-average limited partner units outstanding - diluted (in units)	127,965,000	127,180,000	127,195,000
Earnings per limited partner unit - basic (in dollars per unit)	$ 2.77	$ 4.81	$ 4.39
Earnings per limited partner unit - diluted (in dollars per unit)	$ 2.77	$ 4.81	$ 4.39
Anti-dilutive under the treasury stock method (in units)	1,889,000	2,922,000	3,540,000