SEGMENT INFORMATION - EBITDA Reconciliation (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015		Jun. 30, 2016	Jun. 30, 2015
Reconciliation of consolidated Segment Adjusted EBITDA to net income
Consolidated Segment Adjusted EBITDA	[1]	$ 187,184	$ 199,807	[2]	$ 340,112	$ 408,707	[2]
General and administrative		(18,635)	(18,040)		(36,188)	(35,303)
Depreciation, depletion and amortization		(79,145)	(79,801)		(160,028)	(158,069)
Interest expense, net		(7,766)	(7,701)		(15,377)	(15,138)
Income tax expense (benefit)		(6)	(8)		2	(6)
NET INCOME		$ 81,632	$ 94,257		$ 128,521	$ 200,191

[1] Segment Adjusted EBITDA is defined as net income (prior to the allocation of noncontrolling interest) before net interest expense, income taxes, depreciation, depletion and amortization and general and administrative expenses. Management therefore is able to focus solely on the evaluation of segment operating profitability as it relates to the ARLP Partnership’s revenues and operating expenses, which are primarily controlled by our segments.

[2] Includes equity in loss of affiliates for the three and six months ended June 30, 2015 of $22.0 million and $31.4 million, respectively, in the Illinois Basin segment.