SEGMENT INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended											12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013 segment		Dec. 31, 2012		Dec. 31, 2011
Segment information
Number of reportable segments												5
Number of reportable segments corresponding to major coal producing regions in the eastern U.S.												3
Reportable segment results
Revenues	$ 566,615	[1]	$ 537,136	$ 553,478	$ 547,970	$ 549,318	[1]	$ 511,348	[2]	$ 529,772	$ 443,492	$ 2,205,199	[3]	$ 2,033,930	[3]	$ 1,843,203	[3]
Segment Adjusted EBITDA Expense												1,398,902	[4]	1,338,783	[4]	1,185,047	[4]
Segment Adjusted EBITDA												749,214	[5],[6]	658,463	[5],[6]	622,813	[5],[6]
Total assets	2,126,679	[7]				1,958,840	[7]					2,126,679	[7]	1,958,840	[7]	1,734,477	[7]
Capital expenditures												354,423	[8]	459,232	[8]	372,720	[8]
Additional information
Equity in income (loss) of affiliates												(24,441)		(14,650)		(3,404)
Investments in affiliate	130,410					88,513						130,410		88,513
Payments to affiliate for acquisition and development of coal reserves												25,272		34,601		50,800
Central Appalachia
Segment information
Number of operating segments within the reportable segment												2
White Oak
Segment information
Number of operating segments within the reportable segment												2
Operating segments | Illinois Basin
Reportable segment results
Revenues												1,629,089	[3]	1,499,976	[3]	1,313,148	[3]
Segment Adjusted EBITDA Expense												951,686	[4]	894,769	[4]	786,116	[4]
Segment Adjusted EBITDA												657,404	[5],[6]	593,054	[5],[6]	505,113	[5],[6]
Total assets	1,077,231	[7]				1,042,719	[7]					1,077,231	[7]	1,042,719	[7]	787,923	[7]
Capital expenditures												232,676	[8]	219,029	[8]	153,118	[8]
Operating segments | Central Appalachia
Reportable segment results
Revenues												169,520	[3]	157,311	[3]	206,323	[3]
Segment Adjusted EBITDA Expense												125,323	[4]	131,148	[4]	151,101	[4]
Segment Adjusted EBITDA												43,973	[5],[6]	25,712	[5],[6]	53,729	[5],[6]
Total assets	72,196	[7]				87,068	[7]					72,196	[7]	87,068	[7]	96,099	[7]
Capital expenditures												10,380	[8]	33,817	[8]	28,477	[8]
Operating segments | Northern Appalachia
Reportable segment results
Revenues												377,640	[3]	335,099	[3]	274,233	[3]
Segment Adjusted EBITDA Expense												292,627	[4]	277,736	[4]	203,317	[4]
Segment Adjusted EBITDA												72,594	[5],[6]	47,933	[5],[6]	62,395	[5],[6]
Total assets	525,586	[7]				537,042	[7]					525,586	[7]	537,042	[7]	452,407	[7]
Capital expenditures												63,510	[8]	109,039	[8]	137,040	[8]
Operating segments | White Oak
Reportable segment results
Revenues												2,194	[3]
Segment Adjusted EBITDA Expense												2,112	[4]	(1,347)	[4]	155	[4]
Segment Adjusted EBITDA												(25,229)	[5],[6]	(13,987)	[5],[6]	(4,407)	[5],[6]
Total assets	317,361	[7]				226,714	[7]					317,361	[7]	226,714	[7]	89,690	[7]
Capital expenditures												40,185	[8]	85,671	[8]	51,198	[8]
Additional information
Equity in income (loss) of affiliates												(25,300)		(15,300)		(4,300)
Investments in affiliate	128,700					86,800						128,700		86,800		38,500
Operating segments | Other and Corporate
Reportable segment results
Revenues												39,847	[3]	58,072	[3]	64,667	[3]
Segment Adjusted EBITDA Expense												40,245	[4]	53,005	[4]	59,526	[4]
Segment Adjusted EBITDA												472	[5],[6]	5,751	[5],[6]	5,983	[5],[6]
Total assets	135,380	[7]				66,396	[7]					135,380	[7]	66,396	[7]	309,213	[7]
Capital expenditures												7,672	[8]	11,676	[8]	2,887	[8]
Additional information
Equity in income (loss) of affiliates												900		700		800
Investments in affiliate	1,700					1,700						1,700		1,700		1,600
Elimination
Reportable segment results
Revenues												(13,091)	[3],[9]	(16,528)	[3],[9]	(15,168)	[3],[9]
Segment Adjusted EBITDA Expense												(13,091)	[4],[9]	(16,528)	[4],[9]	(15,168)	[4],[9]
Total assets	$ (1,075)	[7],[9]				$ (1,099)	[7],[9]					$ (1,075)	[7],[9]	$ (1,099)	[7],[9]	$ (855)	[7],[9]

[1] The comparability of our December 31, 2013 and 2012 quarterly results to other quarters presented were affected by a $12.9 million and $14.0 million, respectively, decrease in the ARLP Partnership's workers' compensation liability, excluding discount rate changes, due to the completion of its annual actuarial study, which reflected a favorable development in the ARLP Partnership's disability emergence patterns and claims estimates (Note 17).

[2] During the quarter ended September 30, 2012, the ARLP Partnership recorded a $19.0 million impairment of the carrying value of assets at the Pontiki mine (Note 4).

[3] Revenues included in the Other and Corporate column are primarily attributable to Matrix Group revenues, Mt. Vernon transloading revenues and brokerage sales.

[4] Segment Adjusted EBITDA Expense includes operating expenses, outside coal purchases and other income. Transportation expenses are excluded as these expenses are passed through to the ARLP Partnership's customers and consequently it does not realize any gain or loss on transportation revenues. We review Segment Adjusted EBITDA Expense per ton for cost trends.

[5] 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, asset impairment charge 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.

[6] Includes equity in income (loss) of affiliates for the year ended December 31, 2013, 2012 and 2011 of $(25.3) million, $(15.3) million and $(4.3) million, respectively, included in the White Oak segment and $0.9 million, $0.7 million and $0.8 million, respectively, included in the Other and Corporate segment.

[7] Total assets at December 31, 2013, 2012 and 2011 includes investments in affiliate of $128.7 million, $86.8 million and $38.5 million, respectively, included in the White Oak segment and $1.7 million, $1.7 million and $1.6 million, respectively, included in the Other and Corporate segment.

[8] Capital expenditures shown above for the years ended December 31, 2013, 2012 and 2011 includes $25.3 million, $34.6 million and $50.8 million, respectively, for acquisition and development of coal reserves in our consolidated statements of cash flow. Capital expenditures shown above excludes the Green River acquisition in April 2012 (Note 3).

[9] The elimination column represents the elimination of intercompany transactions and is primarily comprised of sales from Matrix Group to the ARLP Partnership?s mining operations.