Alliance Resource Partners (ARLP) 10-K 27 Feb 25 2024 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2024	Feb. 27, 2025	Jun. 28, 2024
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2024
Securities Act File Number	0-26823
Entity Registrant Name	ALLIANCE RESOURCE PARTNERS LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	73-1564280
Entity Address, Address Line One	1717 South Boulder Avenue, Suite 400
Entity Address, City or Town	Tulsa
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	74119
City Area Code	918
Local Phone Number	295-7600
Title of 12(b) Security	Common Units
Trading Symbol	ARLP
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Document Financial Statement Error Correction [Flag]	false
Entity Common Units Outstanding		128,428,024
Entity Public Float			$ 2,597,152,551
Auditor Name	GRANT THORNTON LLP
Auditor Firm ID	248
Auditor Location	Tulsa, Oklahoma
Entity Central Index Key	0001086600
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
CURRENT ASSETS:
Cash and cash equivalents	$ 136,962	$ 59,813
Trade receivables (net of allowance at December 31, 2024 and 2023 of $2,087 and $300, respectively)	166,829	282,622
Other receivables	10,158	9,678
Inventories, net	120,661	127,556
Advance royalties	11,422	7,780
Digital assets	45,037	9,579
Prepaid expenses and other assets	22,161	19,093
Total current assets	513,230	516,121
PROPERTY, PLANT AND EQUIPMENT:
Property, plant and equipment	4,435,535	4,172,544
Less accumulated depreciation, depletion and amortization	(2,269,265)	(2,149,881)
Total property, plant and equipment, net	2,166,270	2,022,663
OTHER ASSETS:
Advance royalties	70,264	71,125
Equity method investments	35,532	46,503
Equity securities	92,541	92,541
Operating lease right-of-use assets	15,871	16,569
Other long-term assets	22,022	22,904
Total other assets	236,230	249,642
TOTAL ASSETS	2,915,730	2,788,426
CURRENT LIABILITIES:
Accounts payable	98,188	108,269
Accrued taxes other than income taxes	21,051	21,007
Accrued payroll and related expenses	26,946	29,884
Accrued interest	1,821	3,558
Workers' compensation and pneumoconiosis benefits	14,838	15,913
Other current liabilities	48,023	28,498
Current maturities, long-term debt, net	22,275	20,338
Total current liabilities	233,142	227,467
LONG-TERM LIABILITIES:
Long-term debt, excluding current maturities, net	450,885	316,821
Pneumoconiosis benefits	120,152	127,249
Accrued pension benefit		8,618
Workers' compensation	37,177	37,257
Asset retirement obligations	155,156	146,925
Long-term operating lease obligations	13,638	13,661
Deferred income tax liabilities	29,353	33,450
Other liabilities	22,694	18,381
Total long-term liabilities	829,055	702,362
Total liabilities	1,062,197	929,829
COMMITMENTS AND CONTINGENCIES - (Note 16)
ARLP Partners' Capital:
Limited Partners - Common Unitholders 128,061,981 and 127,125,437 units outstanding, respectively	1,867,850	1,896,027
Accumulated other comprehensive loss	(35,103)	(61,525)
Total ARLP Partners' Capital	1,832,747	1,834,502
Noncontrolling interest	20,786	24,095
Total Partners' Capital	1,853,533	1,858,597
TOTAL LIABILITIES AND PARTNERS' CAPITAL	$ 2,915,730	$ 2,788,426

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
CONSOLIDATED BALANCE SHEETS
Trade receivables allowance	$ 2,087	$ 300
Common units outstanding	128,061,981	127,125,437

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SALES AND OPERATING REVENUES:
Revenues	$ 2,448,708	$ 2,566,701	$ 2,419,967
EXPENSES:
Outside coal purchases	35,791	36,149	151
General and administrative	82,224	79,096	80,425
Depreciation, depletion and amortization	285,446	267,982	276,670
Settlement gain			(6,664)
Asset impairments	31,130
Total operating expenses	2,054,579	1,894,304	1,752,524
INCOME FROM OPERATIONS	394,129	672,397	667,443
Interest expense (net of interest capitalized of $12,843, $6,706 and $922, respectively)	(35,229)	(36,091)	(37,331)
Interest income	7,222	9,394	2,035
Equity method investment income (loss)	(4,961)	(1,468)	5,634
Change in fair value of digital assets	22,395
Other income (expense)	(2,062)	218	4,355
INCOME BEFORE INCOME TAXES	381,494	644,450	642,136
INCOME TAX EXPENSE	15,937	8,280	53,978
NET INCOME	365,557	636,170	588,158
LESS: NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTEREST	(4,702)	(6,052)	(1,958)
NET INCOME ATTRIBUTABLE TO ARLP	360,855	630,118	586,200
NET INCOME ATTRIBUTABLE TO ARLP
GENERAL PARTNER		1,384	9,010
LIMITED PARTNERS	$ 360,855	$ 628,734	$ 577,190
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
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - BASIC (in units)	127,964,744	127,180,312	127,195,219
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - DILUTED (in units)	127,965,000	127,180,000	127,195,000
Product
EXPENSES:
Operating expenses (excluding depreciation, depletion and amortization)	$ 1,507,398	$ 1,368,787	$ 1,288,082
Coal sales
SALES AND OPERATING REVENUES:
Revenues	2,111,803	2,210,210	2,102,229
Oil & gas royalties
SALES AND OPERATING REVENUES:
Revenues	138,311	137,751	151,060
Transportation
SALES AND OPERATING REVENUES:
Revenues	112,590	142,290	113,860
EXPENSES:
Operating expenses (excluding depreciation, depletion and amortization)	112,590	142,290	113,860
Other revenues
SALES AND OPERATING REVENUES:
Revenues	$ 86,004	$ 76,450	$ 52,818

CONSOLIDATED STATEMENTS OF IN_2

CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CONSOLIDATED STATEMENTS OF INCOME
Interest expense, interest capitalized	$ 12,843	$ 6,706	$ 922

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NET INCOME	$ 365,557	$ 636,170	$ 588,158
OTHER COMPREHENSIVE INCOME (LOSS):
OTHER COMPREHENSIVE INCOME (LOSS)	26,422	(20,471)	23,175
COMPREHENSIVE INCOME	391,979	615,699	611,333
Less: Comprehensive income attributable to noncontrolling interest	(4,702)	(6,052)	(1,958)
COMPREHENSIVE INCOME ATTRIBUTABLE TO ARLP	387,277	609,647	609,375
Defined benefit pension plan
OTHER COMPREHENSIVE INCOME (LOSS):
Amortization of prior service cost	186	186	186
Net actuarial gain (loss)	8,507	2,894	10,148
Amortization of net actuarial loss	383	682	1,963
Total recognized in accumulated other comprehensive Income	9,076	3,762	12,297
Pneumoconiosis benefits
OTHER COMPREHENSIVE INCOME (LOSS):
Net actuarial gain (loss)	13,990	(25,615)	9,840
Amortization of net actuarial loss	3,356	1,382	1,038
Total recognized in accumulated other comprehensive Income	$ 17,346	$ (24,233)	$ 10,878

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 365,557	$ 636,170	$ 588,158
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	285,446	267,982	276,670
Non-cash compensation expense	10,614	12,864	11,029
Coal inventory adjustment to market	24,568	33,296	364
Equity method investment loss (income)	4,961	1,468	(5,634)
Distributions from equity method investments	2,377	2,567	5,634
Net gain on sale of property, plant and equipment	(262)	(3,230)	(3,665)
Asset impairment	31,130
Change in deferred income tax	(2,185)	(8,973)	34,775
Change in fair value of digital assets	(22,395)
Other non-cash change in digital assets	(10,358)	(12,516)	(307)
Other	20,844	10,316	1,455
Changes in operating assets and liabilities:
Trade receivables	115,793	(41,210)	(108,893)
Other receivables	(1,201)	(1,077)	(7,921)
Inventories, net	(22,243)	(78,004)	(20,138)
Prepaid expenses and other assets	(3,068)	4,108	(5,014)
Advance royalties	(2,781)	(3,636)	(6,787)
Accounts payable	(19,223)	17,842	14,580
Accrued taxes other than income taxes	44	(1,960)	5,180
Accrued payroll and related benefits	(2,938)	(9,739)	2,818
Pneumoconiosis benefits	9,199	3,924	3,849
Workers' compensation	(105)	(1,477)	(3,996)
Other	19,357	(4,484)	20,192
Total net adjustments	437,574	188,061	214,191
Net cash provided by operating activities	803,131	824,231	802,349
Property, plant and equipment:
Capital expenditures	(428,741)	(379,338)	(286,394)
Change in accounts payable and accrued liabilities	9,142	(29,695)	35,956
Proceeds from sale of property, plant and equipment	1,626	3,710	7,468
Contributions to equity method investments	(2,896)	(2,518)	(24,087)
Purchase of equity securities		(49,560)	(42,000)
JC Resources acquisition		(64,999)
Oil & gas reserve business combinations		(14,459)	(92,618)
Oil & gas reserve asset acquisitions	(24,733)	(24,225)
Other	4,938	7,762	(1,663)
Net cash used in investing activities	(440,664)	(553,322)	(403,338)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings under securitization facility	75,000		27,500
Payments under securitization facility	(75,000)		(27,500)
Proceeds from equipment financings	54,626
Payments on equipment financings	(11,981)	(24,970)	(16,071)
Borrowings under revolving credit facilities	20,000
Payments under revolving credit facilities	(20,000)
Borrowing under long-term debt	400,000	75,000
Payments on long-term debt	(299,842)	(129,455)
Payment of debt issuance costs	(11,442)	(12,376)
Payments for purchases of units under unit repurchase program		(19,432)
Payments for purchase of units and tax withholdings related to settlements under deferred compensation plans	(15,544)	(10,334)
Cash settlement of grants under deferred compensation plans	(21,786)
Excess purchase price over the contributed basis from JC Resources acquisition		(7,251)
Cash retained by JC Resources in acquisition		(2,933)	(10,537)
Distributions paid to Partners	(363,430)	(364,579)	(196,347)
Other	(15,919)	(10,789)	(2,436)
Net cash used in financing activities	(285,318)	(507,119)	(225,391)
NET CHANGE IN CASH AND CASH EQUIVALENTS	77,149	(236,210)	173,620
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	59,813	296,023	122,403
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 136,962	$ 59,813	$ 296,023

CONSOLIDATED STATEMENT OF PARTN

CONSOLIDATED STATEMENT OF PARTNERS' CAPITAL - USD ($) $ in Thousands	Limited Partners' Capital Cumulative Effect, Period of Adoption, Adjustment	Limited Partners' Capital	General Partners' Capital	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest	Cumulative Effect, Period of Adoption, Adjustment	Total
Balance at beginning of period at Dec. 31, 2021		$ 1,279,183	$ 68,075	$ (64,229)	$ 11,115		$ 1,294,144
Balance at beginning of period (in units) at Dec. 31, 2021		127,195,219
Comprehensive income:
Net income		$ 577,190	9,010		1,958		588,158
Actuarially determined long-term liability adjustments				23,175			23,175
Total comprehensive income							611,333
Settlement of deferred common unit- based compensation plans (in units)		0
Common unit-based compensation		$ 11,029					11,029
Distributions on deferred common unit-based compensation		(5,553)					(5,553)
Distributions from consolidated company to noncontrolling interest					(1,596)		(1,596)
Profits interest adjustment for noncontrolling interest		(15,030)			15,030
Cash retained by JC Resources in acquisition			(10,537)				(10,537)
Distributions to Partners		(190,794)					(190,794)
Balance at end of period at Dec. 31, 2022		$ 1,656,025	66,548	(41,054)	26,507		1,708,026
Balance at end of period (in units) at Dec. 31, 2022		127,195,219
Comprehensive income:
Net income		$ 628,734	1,384		6,052		636,170
Actuarially determined long-term liability adjustments				(20,471)			(20,471)
Total comprehensive income							615,699
Settlement of deferred common unit- based compensation plans		$ (10,334)					(10,334)
Settlement of deferred common unit- based compensation plans (in units)		860,060
Purchase of units under unit repurchase program		$ (19,432)					(19,432)
Purchase of units under unit repurchase program (in units)		(929,842)
Common unit-based compensation		$ 12,864					12,864
Distributions on deferred common unit-based compensation		(8,530)					(8,530)
Distributions from consolidated company to noncontrolling interest					(8,464)		(8,464)
JC Resources acquisition		(7,251)	(64,999)				(72,250)
Cash retained by JC Resources in acquisition			$ (2,933)				(2,933)
Distributions to Partners		(356,049)					(356,049)
Balance at end of period at Dec. 31, 2023	$ 6,232	$ 1,896,027		(61,525)	24,095	$ 6,232	$ 1,858,597
Balance at end of period (in units) at Dec. 31, 2023		127,125,437					127,125,437
Comprehensive income:
Net income		$ 360,855			4,702		$ 365,557
Actuarially determined long-term liability adjustments				26,422			26,422
Total comprehensive income							391,979
Settlement of deferred common unit- based compensation plans		$ (37,330)					(37,330)
Settlement of deferred common unit- based compensation plans (in units)		936,544
Common unit-based compensation		$ 10,614					10,614
Distributions on deferred common unit-based compensation		(5,514)					(5,514)
Distributions from consolidated company to noncontrolling interest					(8,011)		(8,011)
Distributions to Partners		(357,916)					(357,916)
Other		(5,118)					(5,118)
Balance at end of period at Dec. 31, 2024		$ 1,867,850		$ (35,103)	$ 20,786		$ 1,853,533
Balance at end of period (in units) at Dec. 31, 2024		128,061,981					128,061,981

ORGANIZATION AND PRESENTATION

ORGANIZATION AND PRESENTATION	12 Months Ended
	Dec. 31, 2024
ORGANIZATION AND PRESENTATION
ORGANIZATION AND PRESENTATION	1. ORGANIZATION AND PRESENTATION ​ Significant Relationships Referenced in Notes to Consolidated Financial Statements ​ ● References to “we,” “us,” “our” or “ARLP Partnership” mean the business and operations of Alliance Resource Partners, L.P., the parent company, as well as its consolidated subsidiaries. ● References to “ARLP” mean Alliance Resource Partners, L.P., individually as the parent company, and not on a consolidated basis. ● References to “MGP” mean Alliance Resource Management GP, LLC, ARLP’s general partner. ● References to “Mr. Craft” mean Joseph W. Craft III, the Chairman, President and Chief Executive Officer of MGP. ● References to “Intermediate Partnership” mean Alliance Resource Operating Partners, L.P., the intermediate partnership of Alliance Resource Partners, L.P. ● References to “Alliance Coal” mean Alliance Coal, LLC, an indirect wholly owned subsidiary of ARLP. ● References to “Alliance Minerals” mean Alliance Minerals, LLC, an indirect wholly owned subsidiary of ARLP. ● References to “Alliance Resource Properties” mean Alliance Resource Properties, LLC, an indirect wholly owned subsidiary of ARLP . ​ Organization ​ ARLP is a Delaware limited partnership listed on the NASDAQ Global Select Market under the ticker symbol “ARLP.” ARLP was formed in May 1999 and completed its initial public offering on August 19, 1999 when it acquired substantially all of the coal production and marketing assets of Alliance Resource Holdings, Inc., a Delaware corporation (“ARH”), and its subsidiaries. We are managed by our general partner, MGP, a Delaware limited liability company, which holds a non-economic general partner interest in ARLP. Alliance GP, LLC (“AGP”), which is indirectly wholly owned by Mr. Craft, is the direct owner of MGP. ​ Acquisitions ​ Belvedere ​ On September 9, 2022, we acquired approximately 394 oil & gas net royalty acres in the Delaware Basin from Belvedere Operating, LLC (“Belvedere”) for a purchase price of $11.4 million (the “Belvedere Acquisition”). ​ Jase ​ On October 26, 2022, we acquired approximately 3,928 oil & gas net royalty acres in the Midland and Delaware Basins from Jase Minerals, LP (“Jase”) for a purchase price of $81.2 million (the “Jase Acquisition”). ​ JC Resources ​ On February 22, 2023, we acquired approximately 2,682 oil & gas net royalty acres in the Delaware Basin from JC Resources LP (“JC Resources”), an entity owned by Mr. Craft, for $72.3 million (“JC Resources Acquisition”). ​ Skyland ​ On December 7, 2023, we acquired approximately 2,372 oil & gas net royalty acres in the Anadarko, Williston and Delaware Basins from Skyland Minerals, L.P. (“Skyland”) and Haymaker Minerals & Royalties II, LLC (“Haymaker”) for a purchase price of $14.5 million (“Skyland Acquisition”). ​ The Belvedere, Jase, JC Resources and Skyland Acquisitions enhanced our ownership position in various basins and furthered our business strategy to grow our Oil & Gas Royalties segment through accretive acquisitions. See Note 4 – Acquisitions for more information. We now hold approximately 70,000 net royalty acres in premier oil & gas resource plays including previous acquisitions and our investment in AllDale Minerals III, LP (“AllDale III”). ​ Other Growth Investments ​ Francis ​ On April 5, 2022, we invested $20 million in Francis Renewable Energy, LLC (“Francis”), in the form of a convertible note. Our convertible note matured on April 1, 2023 and was converted into a preferred equity interest in Francis. Francis currently is active in the installation, management and operation of metered-for-fee, public-access electric vehicle (“EV”) charging stations. Francis also develops and constructs EV charging stations for third-party customers. For more information on this investment, please see Note 3 – Variable Interest Entities. ​ Infinitum ​ During 2022, we purchased $42.0 million of Series D Preferred Stock in Infinitum Electric, Inc. (“Infinitum”), a Texas-based startup developer and manufacturer of electric motors featuring printed circuit board stators which have the potential to result in motors that are smaller, lighter, quieter, more efficient and capable of operating at a fraction of the carbon footprint of conventional electric motors. On September 8, 2023, we purchased $24.6 million of Series E Preferred Stock (“Series E Preferred Stock” and, together with the “Series D Preferred Stock,” the “Infinitum Preferred Stock”) in Infinitum. The Infinitum Preferred Stock provides for non-cumulative dividends when and if declared by Infinitum’s board of directors. Each share of Infinitum Preferred Stock is convertible, at any time, at our option, into shares of common stock of Infinitum. For more information on this investment, please see Note 10 – Equity Investments. ​ NGP ET IV ​ On June 2, 2022, we committed to purchasing $25.0 million of limited partner interests in NGP Energy Transition, L.P. (“NGP ET IV”), a private equity fund sponsored by NGP Energy Capital Management, LLC (“NGP”). NGP ET IV focuses on investments that are part of the global transition toward a lower carbon economy by partnering with top-tier management teams and investing growth equity in companies that drive or enable the growth of renewable energy, the electrification of our economy or the efficient use of energy. For more information on this investment, please see Note 3 – Variable Interest Entities. ​ Ascend ​ On August 22, 2023, we purchased $25.0 million of Series D Preferred Stock (the “Ascend Preferred Stock”) in Ascend Elements, Inc. (“Ascend”), a U.S.-based manufacturer and recycler of sustainable, engineered battery materials for electric vehicles. The Ascend Preferred Stock provides for non-cumulative dividends when and if declared by Ascend’s board of directors. Each share is convertible, at any time, at our option, into shares of common stock of Ascend. For more information on this investment please see Note 10 – Equity Investments. ​ The Francis, Infinitum, NGP ET IV and Ascend investments further our business strategy to pursue opportunities that support the growth and development of energy and related infrastructure and leverage our core competencies and build platforms for future lines of business with long-term growth and cash flow generation. ​ Change in Tax Status ​ On March 15, 2022, Alliance Minerals changed its federal income tax status from a pass-through entity to a taxable entity via a “check the box” election (the “Tax Election”), which became effective January 1, 2022. This election for Alliance Minerals reduced the total income tax burden on our oil & gas royalties, as Alliance Minerals now pays entity-level taxes at corporate tax rates which are favorable to our unitholders. For more information on the Tax Election please see Note 22 – Income Taxes. ​ Presentation ​ The consolidated financial statements include the accounts and operations of the ARLP Partnership and present our financial position as of December 31, 2024 and 2023, and results of our operations, comprehensive income, cash flows and changes in partners’ capital for each of the three years in the period ended December 31, 2024. All of our intercompany transactions and accounts have been eliminated. Certain immaterial amounts in the prior period have been reclassified to conform to the current period presentation.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2024
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES ​ Variable Interest Entity (“VIE”) ​ VIEs are primarily entities that lack sufficient equity to finance their activities without additional financial support from other parties or whose equity holders, as a group, lack one or more of the following characteristics: (a) direct or indirect ability to make decisions, (b) obligation to absorb expected losses or (c) right to receive expected residual returns. A VIE must be evaluated quantitatively and qualitatively to determine the primary beneficiary, which is the reporting entity that has (a) the power to direct activities of a VIE that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. The primary beneficiary is required to consolidate the VIE for financial reporting purposes. ​ To determine a VIE’s primary beneficiary, we perform a qualitative assessment to determine which party, if any, has the power to direct activities of the VIE and the obligation to absorb losses and/or receive its benefits. This assessment involves identifying the activities that most significantly impact the VIE’s economic performance and determine whether it, or another party, has the power to direct those activities. When evaluating whether we are the primary beneficiary of a VIE, we perform a qualitative analysis that considers the design of the VIE, the nature of our involvement and the variable interests held by other parties. ​ Business Combinations ​ A business consists of inputs and processes applied to those inputs that have the ability to contribute to the creation of outputs. We account for the acquisition of a business as a business combination, where we record the assets acquired, including identified intangible assets and liabilities assumed at their fair value, which in many instances involves estimates based on third-party valuations, such as appraisals, or internal valuations based on discounted cash flow analyses or other valuation techniques. However, if substantially all the fair value of the assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets with the same risk profile, the acquisition is accounted for as an asset acquisition and recorded at cost. ​ Estimates ​ The preparation of consolidated financial statements in conformity with generally accepted accounting principles of the United States (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts and disclosures in the consolidated financial statements. Actual results could differ from those estimates. Significant estimates and assumptions include: ​ ● Asset retirement obligations; ● Pension obligations; ● Workers’ compensation and pneumoconiosis obligations; ● Acquisition related purchase price allocations; ● Life of mine assumptions; ● Oil & gas reserve quantities and carrying amounts; ● Determination of oil & gas revenue accruals; and ● Contingent consideration liability ​ Fair Value Measurements ​ We apply fair value measurements to certain assets and liabilities. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. Fair value is based on assumptions that market participants would use when pricing an asset or liability, including assumptions about risk and risks inherent in valuation techniques and inputs to valuations. Fair value measurements assume that the transaction occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability (the market for which the reporting entity would be able to maximize the amount received or minimize the amount paid). Valuation techniques used in our fair value measurements are based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect our own market assumptions. ​ We use the following fair value hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value into three broad levels: ​ ● Level 1 – Quoted prices for identical assets and liabilities in active markets that we have the ability to access at the measurement date. ​ ● Level 2 – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model derived valuations whose inputs are observable or whose significant value drivers are observable. ​ ● Level 3 – Unobservable inputs for the asset or liability including situations where there is little, if any, market activity for the asset or liability. ​ The fair value hierarchy gives the highest priority to quoted prices in active markets (Level 1) and the lowest priority to unobservable data (Level 3). In some cases, the inputs used to measure fair value might fall into different levels of the fair value hierarchy. The lowest level input that is significant to a fair value measurement determines the applicable level in the fair value hierarchy. Assessing the significance of a particular input to the fair value measurement requires judgment, considering factors specific to the asset or liability. Significant fair value measurements are used in our significant estimates and are discussed throughout these notes. ​ Cash and Cash Equivalents ​ Cash and cash equivalents include cash on hand and on deposit, including highly liquid investments with maturities of three months or less. At times the ARLP Partnership maintains deposits in federally insured financial institutions in excess of stated federally insured limits. ​ Cash Management ​ The cash flows from operating activities section of our consolidated statements of cash flows reflects adjustments of $3.3 million and $6.7 million representing book overdrafts at December 31, 2024 and 2023, respectively. We did not have material book overdrafts at December 31, 2022. ​ Inventories ​ Coal inventories are stated at the lower of cost or net realizable value on a first-in, first-out basis. Supply, finished goods, work in process and raw materials inventories are stated at an average cost basis, less a reserve for obsolete and surplus items. ​ Advance Royalties ​ Rights to coal mineral leases are often acquired and/or maintained through advance royalty payments. Where royalty payments represent prepayments recoupable against future production, they are recorded as an asset, with amounts expected to be recouped within one year classified as a current asset. As mining occurs on these leases, the royalty prepayments are charged to operating expenses. We assess the recoverability of royalty prepayments based on estimated future production. Royalty prepayments estimated to be nonrecoverable are expensed. Our advance royalties are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Advance royalties, affiliates (see Note 21– Related-Party Transactions) ​ $ 67,189 ​ $ 64,599 ​ Advance royalties, third-parties ​ 14,497 ​ 14,306 ​ Total advance royalties ​ $ 81,686 ​ $ 78,905 ​ ​ Digital Assets ​ We began our crypto-mining activities during the second half of 2020 as we started mining bitcoin as a pilot project to monetize already paid for, yet underutilized, electricity load. We continue to periodically be awarded digital assets through our crypto-mining activities. The awards are accounted for as revenue and valued at the exchange quoted price at the time they are awarded. Beginning January 1, 2024, with our adoption of the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-08, Intangibles - Goodwill and Other - Crypto Assets (Subtopic 350-60) Digital assets Change in fair value of digital assets ​ ​ Property, Plant and Equipment ​ Expenditures which extend the useful lives of existing plant and equipment assets are capitalized. Interest costs associated with major asset additions are capitalized during the construction period. Maintenance and repairs that do not extend the useful life or increase productivity of the asset are charged to operating expense as incurred. Exploration expenditures are charged to operating expense as incurred, including costs related to drilling and study costs incurred to convert or upgrade mineral resources to reserves. Processing facilities and mineral rights, assuming current production estimates, are depreciated or depleted using the units-of-production method. Mining equipment and other plant and equipment assets are depreciated principally using the straight-line method over the remaining estimated life of each mine. Buildings, office equipment and improvements are amortized straight line over their estimated useful lives. Gains or losses arising from retirements are included in operating expenses. Depletion of coal mineral rights is provided on the basis of tonnage mined in relation to estimated recoverable tonnage, which equals estimated proven and probable coal mineral reserves. Therefore, our coal mineral rights are depleted based on only proven and probable coal mineral reserves. See Oil & Gas Reserve Quantities and Carrying Amounts ​ Mine Development Costs ​ Mine development costs are capitalized until production, other than production incidental to the mine development process, commences and are amortized on a units of production method based on the estimated proven and probable coal mineral reserves. Mine development costs represent costs incurred in establishing access to coal mineral reserves and include costs associated with sinking or driving shafts and underground drifts, permanent excavations, roads and tunnels. The end of the development phase and the beginning of the production phase takes place when construction of the mine for economic extraction is substantially complete. Coal extracted during the development phase is incidental to the mine’s production capacity and is not considered to shift the mine into the production phase. ​ Long-Lived Asset Impairment ​ We review the carrying value of long-lived assets and certain identifiable intangibles whenever events or changes in circumstances indicate that the carrying amount of an asset group may not be recoverable based on estimated undiscounted future cash flows. To the extent the carrying amount of an asset group is not recoverable based on undiscounted cash flows, the amount of impairment is measured by the difference between the carrying value and the fair value (See Note 9 – Long-Lived Asset Impairments). ​ Oil & Gas Reserve Quantities and Carrying Amounts ​ We are wholly dependent on third-party operators to explore, develop, produce and operate the properties associated with our mineral interests. We follow the successful efforts method of accounting for our oil & gas mineral interests. Under this method, costs to acquire mineral interests in oil & gas properties are capitalized when incurred. The costs of mineral interests in unproved properties are capitalized pending the results of exploration and leasing efforts by operators. As mineral interests in unproved properties are determined to be proved, the related costs are transferred to proved oil & gas properties. ​ Mineral interests in oil & gas properties are grouped using a reasonable aggregation of properties with a common geological structural feature or stratigraphic condition, which we may also refer to as a depletable group. Mineral interests in proved oil & gas properties are depleted based on the units-of-production method. Proved reserves are quantities of oil & gas that can be estimated with reasonable certainty to be recoverable in the future from a given date forward, from known reservoirs, under existing economic conditions, operating methods, and government regulations. Proved developed resources are the quantities expected to be recovered through the operators’ existing wells with existing equipment, infrastructure and operating methods. ​ We evaluate impairment of our oil & gas mineral interests in proved properties whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. This evaluation is performed on a depletable group basis. We compare the undiscounted projected future cash flows expected in connection with a depletable group to its unamortized carrying amount to determine recoverability. When the carrying amount of a depletable group exceeds its estimated undiscounted future cash flows, the carrying amount is written down to its fair value, which is measured as the present value of the projected future cash flows of such properties. The factors used to determine fair value include estimates of proved reserves, future commodity prices, timing of future production, future expenditures, and a risk-adjusted discount rate. ​ Our oil & gas mineral interests in unproved properties are also assessed for impairment periodically but at least annually when facts and circumstances indicate that the unproved property will not be transferred to proved properties. Impairment of individual unproved properties whose acquisition costs are relatively significant are assessed on a property-by-property basis, and an impairment loss is recognized if we determine that the unproved property will not be transferred to proved properties. Impairment of unproved properties whose acquisition costs are not individually significant are assessed on a group basis. Any amount of loss to be recognized and the amount of a valuation allowance needed to provide for impairment of those properties is determined by amortizing those properties in the aggregate on the basis of historical experience and other relevant information, such as the relative proportion of such properties on which proved reserves have been found in the past. ​ Upon the sale of a complete depletable group, the book value thereof, less proceeds or salvage value, are charged to income. Upon the sale or retirement of an aggregation of interests which make up less than a complete depletable group, the proceeds are credited to accumulated depreciation, depletion and amortization, unless doing so would significantly alter the depreciation, depletion and amortization rate of the depletable group, in which case a gain or loss would be recorded. ​ Equity Investments ​ Our investments and ownership interests in equity securities without readily determinable fair values in entities in which we do not have a controlling financial interest or significant influence are accounted for using a measurement alternative other than fair value which is historical cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for identical or similar investments of the same entity. Distributions received on those investments are recorded as income unless those distributions are considered a return on investment, in which case the historical cost is reduced. We account for our ownership interests in Infinitum and Ascend as equity securities without readily determinable fair values. See Note 10 – Equity Investments for further discussion of these investments. ​ Our investments and ownership interests in entities in which we do not have a controlling financial interest are accounted for under the equity method of accounting if we have the ability to exercise significant influence over the entity. Investments accounted for under the equity method are initially recorded at cost, and the difference between the basis of our investment and the underlying equity in the net assets of the joint venture at the investment date, if any, is amortized over the lives of the related assets that gave rise to the difference. ​ In the event our ownership requires a disproportionate sharing of income or loss, we use the hypothetical liquidation at book value (“HLBV”) method to determine the appropriate allocation of income or loss. Under the HLBV method, income or loss of the investee is allocated based on hypothetical amounts that each investor would be entitled to receive if the net assets held were liquidated at book value at the end of each period, adjusted for any contributions made and distributions received during the period. ​ We hold equity method investments in AllDale III, Francis and NGP ET IV. See Note 3 – Variable Interest Entities and Note 10 – Equity Investments for further discussion of our equity method investments. ​ We review our investments for impairment whenever events or changes in circumstances indicate a loss in the value of the investment may be other-than-temporary. ​ Leases ​ We lease buildings and equipment under operating lease agreements that provide for the payment of minimum rentals. We also have noncancelable lease agreements with third parties for land and equipment under finance lease obligations. Some of our arrangements within these agreements have both lease and non-lease components, which are generally accounted for separately. We have elected a practical expedient to account for lease and non-lease components as a single lease component for leases of buildings and office equipment. Our leases have approximate lease terms of 1 to 32 years, some of which include automatic renewals up to ten years, which are likely to be exercised and some of which include options to terminate the lease within one year. We also hold numerous mineral reserve leases with both related parties as well as third parties, none of which are accounted for as an operating lease or as a finance lease. ​ We review each agreement to determine if an arrangement within the agreement contains a lease at the inception of an arrangement. Once an arrangement is determined to contain an operating or finance lease with a term greater than 12 months, we recognize a lease liability for the obligation to make lease payments and a right-of-use asset for the right to use the underlying asset for the lease term based on the present value of lease payments over the lease term. The lease term includes all noncancelable periods defined in the lease as well as periods covered by options to extend the lease that we are reasonably certain to exercise. As an implicit borrowing rate cannot be determined under most of our leases, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. ​ Expenses related to leases determined to be operating leases will be recognized on a straight-line basis over the lease term including any reasonably assured renewal periods, while those determined to be finance leases will be recognized following a front-loaded expense profile in which interest and amortization are presented separately in the income statement. The determination of whether a lease is accounted for as a finance lease or an operating lease requires management to make estimates primarily about the fair value of the asset and its estimated economic useful life. ​ Common Unit-Based Compensation ​ We maintain the Long-Term Incentive Plan (“LTIP”) for certain key employees and executive officers. Pursuant to the LTIP, unit awards of non-vested “phantom” or notional units, also referred to as “restricted units,” may be granted, which, upon satisfaction of time and performance-based vesting requirements, entitle the LTIP participant to receive ARLP common units. Certain awards may also contain a minimum-value guarantee payable in ARLP common units or cash that would be paid regardless of whether the awards vest, as long as service requirements are met. Annual grant levels, vesting provisions and minimum-value guarantees of restricted units for designated participants are recommended by Mr. Craft, subject to review and approval by the compensation committee of our general partner (“Compensation Committee”). The vesting of all restricted units is subject to the satisfaction of certain financial tests. If it is not probable that the financial tests will be achieved for a particular grant of restricted units, any previously expensed amounts for that grant are reversed, and no future expense will be recognized for that grant other than amounts provided for under minimum-value guarantees. Assuming the financial tests are met, restricted units issued to LTIP participants generally cliff vest on January 1st of the third year following the issuance of such restricted units. We expect to settle restricted unit grants by issuing ARLP common units, except for the portion of the restricted units that will satisfy our tax withholding obligations. We account for forfeitures of non-vested restricted unit grants as they occur. As provided under the distribution equivalent rights (“DERs”) provisions of the LTIP and the terms of the restricted unit awards, all currently outstanding non-vested restricted units include contingent rights to receive quarterly distributions in cash or, at the discretion of the Compensation Committee, phantom units in lieu of cash credited to a bookkeeping account with a value equal to the cash distributions we make to unitholders during the vesting period. If it is not probable the financial tests for a particular grant of restricted units will be met, any previously paid DER amounts for that grant are reversed from Partners’ Capital and recorded as compensation expense and any future DERs, for that grant, if any, will be recognized as compensation expense when paid. ​ The fair value of restricted common unit grants under the LTIP are determined on the grant date of the award and recognized as compensation expense over the requisite service period. The corresponding liability is classified as equity and included in limited partners’ capital in the consolidated financial statements. ​ We utilized the Supplemental Executive Retirement Plan (“SERP”) to provide deferred compensation benefits for certain executive officers. All allocations made to participants under the SERP were made in the form of “phantom” ARLP units. The SERP was administered by the Compensation Committee. ​ Our directors participated in the MGP Amended and Restated Deferred Compensation Plan for Directors (“Directors’ Deferred Compensation Plan”). Pursuant to the Directors’ Deferred Compensation Plan, for amounts deferred either automatically or at the election of the director, a notional account was established and credited with notional common units of ARLP, described in the Directors’ Deferred Compensation Plan as “phantom” units. ​ For both the SERP and Directors’ Deferred Compensation Plan, when quarterly cash distributions were made with respect to ARLP common units, an amount equal to such quarterly distribution was credited to each participant’s notional account as additional phantom units and recorded as compensation expense. All grants of phantom units under the SERP and Directors’ Deferred Compensation Plan vested immediately. ​ On December 16, 2024, the SERP and Directors’ Deferred Compensation Plan were terminated, and final distributions of applicable plan accounts were settled in cash. As of December 31, 2024, we had no further obligations under the SERP or the Directors’ Deferred Compensation Plan. ​ Workers ’ Compensation and Pneumoconiosis (Black Lung) Benefits ​ We are liable for workers’ compensation benefits for traumatic injuries and benefits for black lung disease (or pneumoconiosis). Both traumatic claims and pneumoconiosis benefits are covered through our self-insured programs. ​ We provide income replacement and medical treatment for work-related traumatic injury claims as required by applicable state laws. Workers’ compensation laws also compensate survivors of workers who suffer employment related deaths. Our liability for traumatic injury claims is the estimated present value of current workers’ compensation benefits, based on our actuarial estimates. Our actuarial calculations are based on a blend of actuarial projection methods and numerous assumptions including claim development patterns, mortality, medical costs and interest rates. ​ Our pneumoconiosis benefits liability is calculated using the service cost method based on the actuarial present value of the estimated pneumoconiosis obligation. Our actuarial calculations are based on numerous assumptions including claim development patterns, medical costs and mortality. Actuarial gains or losses are amortized over the remaining service period of active miners. ​ Pension Benefits ​ The funded status of our pension benefit plan is recognized separately in our consolidated balance sheets as either an asset or liability. The funded status is the difference between the fair value of plan assets and the plan’s benefit obligation. Pension obligations and net periodic benefit costs are actuarially determined and impacted by various assumptions and estimates including expected return on assets, discount rates, mortality assumptions, employee turnover rates and retirement dates. We evaluate our assumptions periodically and make adjustments to these assumptions and the recorded liability as necessary. ​ The discount rate is determined for our pension benefit plan based on an approach specific to our plan. The year end discount rate is determined considering a yield curve comprised of high-quality corporate bonds and the timing of the expected benefit cash flows. ​ The expected long-term rate of return on plan assets is determined based on broad equity and bond indices, the investment goals and objectives, the target investment allocation and on the average annual total return for each asset class. ​ Unrecognized actuarial gains and losses and unrecognized prior service costs and credits are deferred and recorded in accumulated other comprehensive loss until amortized as a component of net periodic benefit cost. Unrecognized actuarial gains and losses in excess of 10% of the greater of the benefit obligation or the market-related value of plan assets are amortized over the participants’ average remaining future years of service. ​ Asset Retirement Obligations ​ Our coal mining operations are governed by various state statutes and the Federal Surface Mining Control and Reclamation Act of 1977, which establish reclamation and mine closing standards. These regulations require, among other things, restoration of property in accordance with specified standards and an approved reclamation plan. We record a liability for the fair value of an asset retirement obligation in the period incurred or acquired and a corresponding amount is capitalized as part of the related long-lived asset and depreciated on a units-of-production basis. As changes in estimates occur (such as mine plan revisions, changes in estimated costs or changes in anticipated timing of reclamation activities), adjustments to the obligation and asset are recognized at the present value of the change in obligation. For locations that have been fully depleted or closed, the present value of the change in obligation is recorded to operating expense. Accretion of the asset retirement obligation is recognized over time and until reclamation obligations are satisfied. ​ Asset retirement obligations primarily relate to mine site reclamation activities, which includes permanently sealing portals at underground mines, reclaiming the final pits for both our underground mines and past surface mines, removing or covering refuse piles and settling ponds, water treatment, and dismantling preparation plants, other facilities and roadway infrastructure. Federal and state laws require bonds to secure our obligations to reclaim lands used for mining and are typically renewed on an annual basis. ​ Coal Revenue Recognition ​ Revenues from coal supply contracts with customers, which primarily relate to sales of thermal coal, are recognized at the point in time when control of the coal passes to the customer. We have determined that each ton of coal represents a separate and distinct performance obligation. Our coal supply contracts and other revenue contracts vary in length from short-term to long-term sales contracts and do not typically have significant financing components. Transportation revenues represent the fulfillment costs incurred for the services provided to customers through third-party carriers and for which we are directly reimbursed. Other revenues primarily consist of transloading fees, administrative service revenues from our affiliates, mine safety services and products, other coal contract fees and other handling and service fees. Performance obligations under these contracts are typically satisfied upon transfer of control of the goods or services to our customer which is determined by the contract and could be upon shipment or upon delivery. ​ The estimated transaction price from each of our contracts is based on the total amount of consideration we expect to be entitled to under the contract. Included in the transaction price for certain coal supply contracts is the impact of variable consideration, including quality price adjustments, handling services, government imposition claims, per ton price fluctuations based on certain coal sales price indices and anticipated payments in lieu of shipments. We have constrained the expected value of variable consideration in our estimation of transaction price and only included this consideration to the extent that it is probable that a significant revenue reversal will not occur. The estimated transaction price for each contract is allocated to our performance obligations based on relative standalone selling prices determined at contract inception. Variable consideration is allocated to a specific part of the contract in many instances, such as if the variable consideration is based on production activities for coal delivered during a certain period or the outcome of a customer’s ability to accept coal shipments over a certain period. ​ Contract assets are recorded as trade receivables and reported separately in our consolidated balance sheet from other contract assets as title passes to the customer and our right to consideration becomes unconditional. Payments for coal shipments are typically due within two four weeks ​ Oil & Gas Revenue Recognition ​ Oil & gas royalty revenues are recognized at the point in time when control of the product is transferred to the purchaser by the lessee and collectability of the sales price is reasonably assured. Oil & gas are priced on the delivery date based on prevailing market prices with certain adjustments related to oil quality and physical location. The royalty we receive is tied to a market index, with certain adjustments based on, among other factors, whether a well connects to a gathering or transmission line, quality and heat content of the product, and prevailing supply and demand conditions. ​ We also periodically earn revenue from lease bonuses. We recognize lease bonus revenue when we execute a lease of our mineral interests to exploration and production companies. A lease agreement represents our contract with an operator, which is generally an exploration and production company. The contract will (a) generally transfer the rights to any oil or gas discovered, (b) grant us a right to a specified royalty interest from the operator, and (c) require the operator to commence drilling and complete operations within a specified time period. Control of the minerals transfers to the operator when the lease agreement is executed. At the time we execute the lease agreement, we expect to receive the lease bonus payment within a reasonable time, though in no case more than one year, such that we do not adjust the expected amount of consideration for the effects of any significant financing component. ​ As a non-operator, we have limited visibility into the timing of when new wells start producing. In addition, production statements may not be received for 30 to 90 days or more after the date production is delivered. As a result, we are required to estimate the amount of production delivered to the purchaser and the price that will be received for the sale of the product. The expected sales volumes and prices from our properties are estimated and recorded within the Trade receivables ​ Income Taxes ​ We are not a taxable entity for federal or state income tax purposes; the tax effect of our activities accrues to our unitholders. Although publicly traded partnerships as a

VARIABLE INTEREST ENTITIES

VARIABLE INTEREST ENTITIES	12 Months Ended
	Dec. 31, 2024
VARIABLE INTEREST ENTITIES
VARIABLE INTEREST ENTITIES	3. VARIABLE INTEREST ENTITIES ​ AllDale I & II and Cavalier Minerals ​ We own the general partner interests and, including the limited partner interests we hold through our ownership in Cavalier Minerals JV, LLC (“Cavalier Minerals”), approximately 97% of the limited partner interests in AllDale Minerals LP (“AllDale I”) and AllDale Minerals II, LP (“AllDale II”, and collectively with AllDale I, “AllDale I & II”). As the general partner of AllDale I & II, we are entitled to receive 20.0% of all distributions from AllDale I & II with the remaining 80.0% allocated to limited partners based upon ownership percentages. ​ Cavalier Minerals owns approximately 72% of the limited partner interests in AllDale I & II. We own the managing member interest and a 96% member interest in Cavalier Minerals. Bluegrass Minerals Management, LLC (“Bluegrass Minerals”) owns a 4% member interest in Cavalier Minerals and a profits interest which entitles it to receive distributions equal to 25% of all distributions (including in liquidation) after all members have recovered their investment. All members have recovered their investment and Bluegrass Minerals began receiving its profits interest distributions in late 2022. ​ We have concluded that AllDale I, AllDale II and Cavalier Minerals are VIEs which we consolidate as the primary beneficiary because we have the power to direct the activities that most significantly impact the economic performance of AllDale I, AllDale II and Cavalier Minerals in addition to having substantial equity ownership. ​ Our share of Cavalier Minerals’ investment in AllDale I & II is eliminated in consolidation and Bluegrass Minerals’ investment in Cavalier Minerals is accounted for as noncontrolling ownership interest in our consolidated balance sheets. Additionally, earnings attributable to Bluegrass Minerals are recognized as noncontrolling interest in our consolidated statements of income. ​ The following table presents the carrying amounts and classification of AllDale I & II’s assets and liabilities included in our consolidated balance sheets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ Assets (liabilities): (in thousands) Cash and cash equivalents ​ $ 5,154 ​ $ 4,690 ​ Trade receivables ​ 11,209 ​ 16,058 ​ Total property, plant and equipment, net ​ 373,093 ​ 389,767 ​ Accounts payable ​ ​ (221) ​ ​ (175) ​ Accrued taxes other than income taxes ​ (870) ​ ​ (958) ​ ​ AllDale III ​ AllDale III owns oil & gas mineral interests in areas around the oil & gas mineral interests we own. Alliance Minerals owns a 13.9% limited partner interest in AllDale III. Alliance Minerals’ investment in AllDale III is subject to a 25% profits interest for the general partner that is subject to a return hurdle equal to the greater of 125% of cumulative capital contributions and a 10% internal rate of return, and following an 80/20 “catch-up” provision for the general partner. ​ We have concluded that AllDale III is a VIE that we do not consolidate. AllDale III is structured as a limited partnership with the limited partners (1) not having the ability to remove the general partner and (2) not participating significantly in the operational decisions. We are not the primary beneficiary of AllDale III because we do not have the power to direct the activities that most significantly impact AllDale III’s economic performance. At December 31, 2024, the carrying value of our investment in AllDale III was $22.5 million. ​ Francis ​ On April 5, 2022, we invested $20 million in Francis, in the form of a convertible note. Our convertible note matured on April 1, 2023 and was converted into a preferred equity interest in Francis. Prior to conversion, we had determined the note more closely represented equity as opposed to debt. Therefore, we accounted for the convertible note as an equity contribution even though we did not participate in Francis’ earnings or losses and were not eligible to receive distributions during the term of the note. Subsequent to the conversion on April 1, 2023, we participate in earnings and losses and are eligible to receive distributions. As of December 31, 2024, we held approximately 16.7% of Francis’ equity. ​ We have concluded that Francis is a VIE that we do not consolidate. Francis’ management structure is similar to a limited partnership with the non-managing members (i) not having the ability to remove the managing member and (ii) not participating significantly in the operational decisions. We are not the primary beneficiary of Francis because we do not have the power to direct the activities that most significantly impact Francis’s economic performance. At December 31, 2024, the carrying value of our investment in Francis was $4.3 million. ​ NGP ET IV ​ On June 2, 2022, we committed to purchase $25.0 million of limited partner interests in NGP ET IV, a private equity fund sponsored by NGP and focused on investments that are part of the global transition toward a lower carbon economy. This commitment represents a 3.6% interest in NGP ET IV. As of December 31, 2024, we have funded $9.5 million of this commitment. ​ We have concluded that NGP ET IV is a VIE that we do not consolidate. NGP ET IV is structured as a limited partnership with limited partners (i) not having the ability to remove the general partner and (ii) not participating significantly in the operational decisions. We are not the primary beneficiary of NGP ET IV because we do not have the power to direct the activities that most significantly impact NGP ET IV’s economic performance. At December 31, 2024, the carrying value of our investment in NGP ET IV was $8.8 million.

ACQUISITIONS

ACQUISITIONS	12 Months Ended
	Dec. 31, 2024
ACQUISITIONS
ACQUISITIONS	4. ACQUISITION S ​ Belvedere ​ On September 9, 2022 (the “Belvedere Acquisition Date”), we acquired approximately 394 oil & gas net royalty acres in the Delaware Basin from Belvedere for a cash purchase price of $11.4 million, which was funded with cash on hand. This acquisition gives us additional exposure to a productive area of the Delaware Basin and is within close proximity to reserves that we currently own. Because the mineral interests acquired in the Belvedere Acquisition include royalty interests in both developed properties and undeveloped properties with different risk profiles, we have determined that the acquisition should be accounted for as a business combination and the underlying assets should be recorded at fair value as of the Belvedere Acquisition Date on our consolidated balance sheet. ​ The following table summarizes the fair value allocation of assets acquired as of the Belvedere Acquisition Date: ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 7,724 ​ Mineral interests in unproved properties ​ ​ 3,667 ​ ​ ​ $ 11,391 ​ ​ The fair value of the mineral interests was determined using an income approach consisting of a discounted cash flow model. The assumptions used in the discounted cash flow model included estimated production, projected cash flows, forward oil & gas prices and risk adjusted discount rates. Certain assumptions used are not observable in active markets; therefore, the fair value measurements represent Level 3 fair value measurements. ​ The amounts of revenue and earnings from the mineral interests acquired in the Belvedere Acquisition included in our consolidated statements of income from the Belvedere Acquisition Date through December 31, 2022 are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2022 ​ (in thousands) ​ ​ ​ ​ Revenue $ 722 ​ Net income 488 ​ ​ The following represents our supplemental pro forma consolidated revenue and net income for the year ended December 31, 2022 as if the mineral interests acquired in the Belvedere Acquisition had been included in our consolidated results since January 1, 2022. These amounts have been calculated after applying our accounting policies. ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,420,824 ​ Net income ​ ​ 588,916 ​ ​ Jase ​ On October 26, 2022 (the “Jase Acquisition Date”), we acquired approximately 3,928 oil & gas net royalty acres in the Midland and Delaware Basins from Jase for a cash purchase price of $81.2 million which was funded with cash on hand. This acquisition further enhanced our ownership position in the Permian Basin. Because the mineral interests acquired in the Jase Acquisition include royalty interests in both developed properties and undeveloped properties with different risk profiles, we have determined that the acquisition should be accounted for as a business combination and the underlying assets should be recorded at fair value as of the Jase Acquisition Date on our consolidated balance sheet. ​ The following table summarizes the fair value allocation of assets acquired as of the Jase Acquisition Date: ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 35,918 ​ Mineral interests in unproved properties ​ ​ 43,740 ​ Receivables ​ ​ 1,569 ​ Net assets acquired ​ $ 81,227 ​ ​ The fair value of the mineral interests was determined using an income approach consisting of a discounted cash flow model. The assumptions used in the discounted cash flow model included estimated production, projected cash flows, forward oil & gas prices and risk adjusted discount rates. The fair value of the receivables was determined using estimated production during the period between the Jase Acquisition Date and the effective date of the agreement and observable sales prices during the period. Certain assumptions used are not observable in active markets; therefore, the fair value measurements represent Level 3 fair value measurements. ​ The amounts of revenue and earnings from the mineral interests acquired in the Jase Acquisition included in our consolidated statements of income from the Jase Acquisition Date through December 31, 2022 are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2022 ​ (in thousands) ​ ​ ​ ​ Revenue $ 1,689 ​ Net income 854 ​ ​ The following represents our supplemental pro forma consolidated revenue and net income for the year ended December 31, 2022 as if the mineral interests acquired in the Jase Acquisition had been included in our consolidated results since January 1, 2022. These amounts have been calculated after applying our accounting policies. ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,430,734 ​ Net income ​ ​ 596,759 ​ ​ JC Resources ​ On February 22, 2023, we completed the JC Resources Acquisition, which gives us increased exposure to a prolific area of the Delaware Basin that is within close proximity to reserves that we currently own. This acquisition was approved by the conflicts committee of MGP’s board of directors, which is comprised entirely of independent directors. Because JC Resources is under common control with us, we recorded the acquisition at JC Resources’ carrying value for each period presented. The carrying value of the mineral interests as well as related receivables and payables at February 22, 2023 was $65.0 million inclusive of $25.4 million and $37.8 million of mineral interests in proved and unproved properties, respectively. ​ Acquisition Agreement ​ During 2023 and 2024, we were party to a collaborative agreement with a third party for the acquisition of oil & gas mineral interests in the Midland and Delaware Basins. Under the agreement, the third party assists us in the identification, evaluation, and acquisition of target oil & gas mineral interests. In exchange for these services, the third party receives a participation share, partially funded by the third party, and is paid a periodic management fee. Pursuant to this agreement, we purchased $5.8 million and $10.7 million of oil & gas mineral interests in proved and unproved properties, respectively, during the year ended December 31, 2024 and $6.5 million and $6.7 million in proved and unproved properties, respectively, during the year ended December 31, 2023. Management fees paid under this agreement have been immaterial. ​ Skyland Acquisition ​ On December 7, 2023 (the “Skyland Acquisition Date”), we acquired approximately 2,372 oil & gas net royalty acres in the Anadarko, Williston and Delaware Basins from Skyland and Haymaker for a cash purchase price of $14.5 million which was funded with cash on hand. This acquisition further enhanced our ownership position in these basins. Because the mineral interests acquired in the Skyland Acquisition include royalty interests in both developed properties and undeveloped properties with different risk profiles, we have determined that the acquisition should be accounted for as a business combination and the underlying assets should be recorded at fair value as of the Skyland Acquisition Date on our consolidated balance sheet. ​ The following table summarizes the fair value allocation of assets acquired as of the Skyland Acquisition Date: ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 8,694 ​ Mineral interests in unproved properties ​ ​ 5,765 ​ Net assets acquired ​ $ 14,459 ​ ​ The fair value of the mineral interests was determined using an income approach consisting of a discounted cash flow model. The assumptions used in the discounted cash flow model included estimated production, projected cash flows, forward oil & gas prices and risk adjusted discount rates. Certain assumptions used are not observable in active markets; therefore, the fair value measurements represent Level 3 fair value measurements. ​ The amounts of revenue and earnings from the mineral interests acquired in the Skyland Acquisition included in our consolidated statements of income from the Skyland Acquisition Date through December 31, 2023 are immaterial. ​ The following represents our supplemental pro forma consolidated revenues and net income for the years ended December 31, 2023 and 2022 as if the mineral interests acquired in the Skyland Acquisition had been included in our consolidated results since January 1, 2022. These amounts have been calculated after applying our accounting policies. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2023 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,568,516 ​ $ 2,423,313 ​ Net income ​ ​ 637,757 ​ ​ 591,140 ​ ​ Miscellaneous Acquisitions ​ In addition to the acquisitions discussed above, we purchased $1.3 million and $6.9 million of oil & gas mineral interests in proved and unproved properties, respectively, during the year ended December 31, 2024, $6.8 million and $4.3 million in proved and unproved properties, respectively, during the year ended December 31, 2023 and $1.3 million and $0.4 million in proved and unproved properties, respectively, during the year ended December 31, 2022.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2024
FAIR VALUE MEASUREMENTS
FAIR VALUE MEASUREMENTS	5. FAIR VALUE MEASUREMENTS ​ The following table summarizes certain fair value measurements within the hierarchy not included elsewhere in these notes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value ​ ​ Carrying Value Level 1 Level 2 Level 3 ​ ​ (in thousands) ​ December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recorded on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Digital assets (1) ​ $ 45,037 ​ $ 45,037 ​ $ — ​ $ — ​ Contingent consideration ​ $ 13,100 ​ $ — ​ $ — ​ $ 13,100 ​ Additional disclosures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term debt ​ $ 490,387 ​ $ — ​ $ 523,461 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recorded on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent consideration ​ $ 9,900 ​ $ — ​ $ — ​ $ 9,900 ​ Additional disclosures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term debt ​ $ 347,584 ​ $ — ​ $ 347,116 ​ $ — ​ (1) As discussed in Note 2 – Summary of Significant Accounting Policies, we adopted ASU 2023-08 effective January 1, 2024. Prior to our adoption, our digital assets were not recorded at fair value on a recurring basis. ​ The carrying amounts for cash equivalents, accounts receivable, accounts payable, accrued and other liabilities, approximate fair value due to the short maturity of those instruments. ​ The fair value of our digital assets is based on an exchange quoted price. See Note 7 – Digital Assets for more information on our digital assets. ​ The fair value measurement of our contingent consideration liability is determined using an option approach methodology simulation based on significant inputs not observable in active markets representing a Level 3 fair value measurement under the fair value hierarchy. Our contingent consideration liability is associated with our acquisition of our Hamilton mine in 2015 wherein we agreed to pay the seller additional consideration for the acquisition if the average quarterly sales price exceeds a defined threshold price in any future quarters subject to a maximum of $110.0 million reduced for any payments made under an overriding royalty agreement with the sellers relating to mineral interests controlled by our Hamilton mine. We have paid $9.6 million under this contingent consideration agreement and nothing under the overriding royalty agreement as of December 31, 2024. ​ The estimated fair value of our long-term debt, including current maturities, is based on interest rates that we believe are currently available to us in active markets for issuance of debt with similar terms and remaining maturities. See Note 12 – Long-Term Debt for additional information on our long-term debt. ​ Quantitative Information about Level 3 Fair Value Measurements ​ Our option approach methodology simulation generates an expected payment for each quarter in Hamilton’s mine life by using proprietary internal estimates of our uncommitted coal sales prices and generating a simulated uncommitted coal sales price by applying unobservable inputs through a million simulations. This simulated coal sales price is then used in a calculation of the expected future payments using our proprietary committed coal sales prices and production for each quarter. We then calculate the present value of the estimated future payments. The following table presents quantitative information about certain significant unobservable inputs used in the fair value measurement for our contingent consideration liability. The use of significant unobservable inputs results in uncertainty as of the reporting date, as changes in these unobservable inputs could significantly raise or lower the estimated fair value. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Valuation Technique(s) Unobservable Input Range/Amount (Average) (a) ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent Consideration ​ Option approach methodology simulation ​ Cost of Debt ​ 6.51% - 8.56% ​ ​ ​ ​ ​ Coal price volatility ​ 6.2% ​ ​ ​ ​ ​ Market price of risk adjustment (annual) ​ 6.2% ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent Consideration ​ Option approach methodology simulation ​ Cost of Debt ​ 7.27% - 9.08% ​ ​ ​ ​ ​ Coal price volatility ​ 6.3% ​ ​ ​ ​ ​ Market price of risk adjustment (annual) ​ 7.8% ​ ​ ​ ​ ​ ​ ​ ​ ​ (a) Averages represent the arithmetic average of the inputs and is not weighted by a relative fair value or notional amount ​ ​ The following table represents changes in our contingent consideration liability: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 ​ 2023 ​ ​ (in thousands) ​ Beginning balance ​ $ 9,900 ​ $ 10,100 ​ Noncash changes in fair value (1) ​ ​ 10,989 ​ ​ 1,650 ​ Payments ​ ​ (7,789) ​ ​ (1,850) ​ Ending balance ​ $ 13,100 ​ $ 9,900 ​ (1) Noncash changes in the fair value of our continent consideration liability are included in the Operating expenses (excluding depreciation, depletion and amortization) line item within our consolidated statements of income.

INVENTORIES

INVENTORIES	12 Months Ended
	Dec. 31, 2024
INVENTORIES
INVENTORIES	6. INVENTORIES ​ Inventories consist of the following : ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal ​ $ 37,290 ​ $ 56,549 ​ Finished goods (net of reserve for obsolescence of $2,481 and $2,188, respectively) ​ ​ 14,197 ​ ​ 11,752 ​ Work in process ​ ​ 1,560 ​ ​ 2,379 ​ Raw materials ​ ​ 7,192 ​ ​ 6,448 ​ ​ ​ ​ 60,239 ​ ​ 77,128 ​ Supplies (net of reserve for obsolescence of $6,409 and $5,979, respectively) ​ 60,422 ​ 50,428 ​ Total inventories, net ​ $ 120,661 ​ $ 127,556 ​ ​ The above balances reflect lower of cost or net realizable value adjustments of $24.6 million to our coal inventories. These adjustments are a result of lower coal sale prices and higher cost per ton primarily due to a longwall move at the Hamilton County Coal, LLC (“Hamilton”) mining complex, lower production at Mettiki Coal , LLC and Mettiki Coal (WV), LLC (collectively “Mettiki”) and MC Mining, LLC (“MC Mining”) mining complexes, and ongoing development activities at the Henderson County mine at our River View Coal, LLC (“River View”) mining complex. ​ Certain of our subsidiaries, primarily consisting of Matrix Design Group, LLC, its subsidiaries, and Alliance Design Group, LLC (collectively referred to as “Matrix Group”), manufacture a variety of products for our mining operations and third parties. Historically, these products were primarily consumed by our mining operations with the associated inventory presented as supplies inventory. Recently Matrix Group has been increasing its sales to third-parties. As a result, we have presented our manufactured goods inventories in the table above separately from our historical presentation of supplies inventory.

DIGITAL ASSETS

DIGITAL ASSETS	12 Months Ended
	Dec. 31, 2024
DIGITAL ASSETS
DIGITAL ASSETS	7. DIGITAL ASSETS ​ The following table sets forth our digital assets as shown on the consolidated balance sheet: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ ​ ​ Units ​ Cost Basis ​ Fair Value ​ Digital assets: ​ (in thousands, except unit data) ​ Bitcoin ​ ​ 481.89 ​ $ 18,748 ​ $ 45,037 ​ Total ​ ​ ​ ​ $ 18,748 ​ $ 45,037 ​ ​ The following table represents a reconciliation of the fair values of our digital assets: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ ​ 2024 ​ Digital assets: ​ (in thousands) ​ Beginning balance ​ $ 15,811 ​ Additions ​ ​ 10,428 ​ Dispositions ​ ​ (3,597) ​ Fair value gains ​ ​ 22,395 ​ Ending balance ​ $ 45,037 ​ ​ As discussed in Note 2 – New Accounting Standards, our beginning balance is inclusive of a cumulative-effect adjustment of $6.2 million as of January 1, 2024. Additions are the result of awarded digital assets received from our crypto-mining activities, while dispositions are the result of sales and payments for services. During the year ended December 31, 2024, we had digital asset dispositions of $3.6 million, inclusive of realized gains of $2.1 million.

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Dec. 31, 2024
PROPERTY, PLANT AND EQUIPMENT
PROPERTY, PLANT AND EQUIPMENT	8. PROPERTY, PLANT AND EQUIPMENT ​ Property, plant and equipment consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Mining equipment and processing facilities ​ $ 2,131,697 ​ $ 1,989,541 ​ Land and coal mineral rights ​ 508,892 ​ 504,736 ​ Oil & gas mineral interests ​ ​ 878,083 ​ ​ 853,350 ​ Buildings, office equipment, improvements and other miscellaneous equipment ​ 315,092 ​ 310,876 ​ Construction, mine development and other projects in progress ​ 213,579 ​ 184,895 ​ Mine development costs ​ 388,192 ​ 329,146 ​ Property, plant and equipment, at cost ​ 4,435,535 ​ 4,172,544 ​ Less accumulated depreciation, depletion and amortization ​ (2,269,265) ​ (2,149,881) ​ Total property, plant and equipment, net ​ $ 2,166,270 ​ $ 2,022,663 ​ ​ All of our property, plant and equipment have depreciable lives of 1 to 33 years. Depreciation, depletion and amortization expense related to property, plant and equipment was $287.1 million, $276.4 million and $273.8 million for the years ended December 31, 2024, 2023 and 2022, respectively. ​ At December 31, 2024 and 2023, land and coal mineral rights above include $14.1 million and $13.4 million, respectively, of carrying value associated with coal mineral reserves and resources attributable to properties where we or a third party to which we lease coal mineral reserves and resources are not currently engaged in mining operations or leasing to third parties, and therefore, the coal mineral reserves are not currently being depleted. We believe that the carrying value of these coal mineral reserves will be recovered. ​ At December 31, 2024 and 2023, our oil & gas mineral interests noted in the table above include the carrying value of our unproved oil & gas mineral interests totaling $377.5 million and $411.6 million, respectively. We generally do not record depletion expense for our unproved oil & gas mineral interests; however, we do review for impairment as needed throughout the year. ​ We incurred $67.2 million and $44.4 million in mine development costs, primarily related to Tunnel Ridge, LLC (“Tunnel Ridge”) mining complex and the Henderson County mine at River View for the years ended December 31, 2024 and 2023 respectively. All past capitalized mine development costs are associated with other mines that shifted to the production phase in past years and we are amortizing these costs accordingly. We believe that the carrying value of the past development costs will be recovered.

LONG-LIVED ASSET IMPAIRMENTS

LONG-LIVED ASSET IMPAIRMENTS	12 Months Ended
	Dec. 31, 2024
LONG-LIVED ASSET IMPAIRMENTS
LONG-LIVED ASSET IMPAIRMENTS	9. LONG-LIVED ASSET IMPAIRMENTS ​ On November 15, 2024, we issued Worker Adjustment and Retraining Notification Act notices to the employees of our MC Mining, LLC (“MC Mining”) mining complex, which is primarily included in our Appalachia Coal Operations reportable segment. The notices were issued primarily in response to market uncertainty, challenging geology and higher costs which has led to the decision to reduce production at the mine. Accordingly, we adjusted the carrying value of MC Mining’s assets from $101.3 million to its fair value of $70.2 million resulting in an impairment charge of $31.1 million. ​ The fair value of the impaired assets was determined using a cost replacement approach, which represents a Level 3 fair value measurement under the fair value hierarchy. The fair value analysis used quoted prices obtained from external sources as adjusted to account for the remaining useful life of the assets.

EQUITY INVESTMENTS

EQUITY INVESTMENTS	12 Months Ended
	Dec. 31, 2024
EQUITY INVESTMENTS
EQUITY INVESTMENTS	10. EQUITY INVESTMENTS ​ Equity Method Investments ​ We account for our ownership interest in the income or loss of AllDale III, Francis and NGP ET IV as equity method investments. We record equity income or loss based on the distribution structure of the investments. The changes in our equity method investments were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ Beginning balance ​ $ 46,503 ​ $ 49,371 ​ $ 26,325 ​ Contributions ​ ​ 2,896 ​ ​ 2,518 ​ ​ 24,087 ​ Equity method investment income (loss) ​ ​ (4,961) ​ ​ (1,468) ​ ​ 5,634 ​ Distributions received ​ ​ (3,788) ​ ​ (3,918) ​ ​ (6,675) ​ Change in our share of net assets ​ ​ (5,118) ​ ​ — ​ ​ — ​ Ending balance ​ $ 35,532 ​ $ 46,503 ​ $ 49,371 ​ ​ Equity method investment income (loss) represents our share of the income or loss of the equity method investments. ​ Change in our share of net assets represents a reduction in our position in the investments due to additional capital contributions from other investors. ​ Infinitum ​ During 2022, we purchased $42.0 million of Series D Preferred Stock in Infinitum, a Texas-based startup developer and manufacturer of electric motors featuring printed circuit board stators. On September 8, 2023, we purchased $24.6 million of Series E Preferred Stock in Infinitum. The Infinitum Preferred Stock provides for non-cumulative dividends when and if declared by Infinitum’s board of directors. Each share of Infinitum Preferred Stock is convertible, at any time, at our option, into shares of common stock of Infinitum. We account for our ownership interest in Infinitum as an equity investment without a readily determinable fair value. Absent an observable price change, it is not practicable to estimate the fair value of our investment in Infinitum because of the lack of a quoted market price for our ownership interests. Therefore, we use a measurement alternative other than fair value to account for our investment. ​ Ascend ​ On August 22, 2023, we purchased $25.0 million of Ascend Preferred Stock in Ascend, a U.S.-based manufacturer and recycler of sustainable, engineered battery materials for electric vehicles. The Ascend Preferred Stock provides for non-cumulative dividends when and if declared by Ascend’s board of directors. Each share is convertible, at any time, at our option, into shares of common stock of Ascend. We account for our ownership interest in Ascend as an equity investment without a readily determinable fair value. Absent an observable price change, it is not practicable to estimate the fair value of our investment in Ascend because of the lack of a quoted market price for our ownership interests. Therefore, we use a measurement alternative other than fair value to account for our investment.

LEASES

LEASES	12 Months Ended
	Dec. 31, 2024
LEASES
LEASES	11. LEASES ​ The components of lease expense were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of right-of-use assets ​ $ 95 ​ $ 96 ​ $ 597 ​ Interest on lease liabilities ​ 22 ​ 27 ​ 73 ​ Operating lease cost ​ 3,573 ​ 3,572 ​ 2,884 ​ Short-term lease cost ​ ​ — ​ ​ — ​ ​ — ​ Variable lease cost ​ 1,694 ​ 1,680 ​ 1,665 ​ Total lease cost ​ $ 5,384 ​ $ 5,375 ​ $ 5,219 ​ ​ Rental expense was $7.4 million, $5.7 million and $5.1 million for the years ended December 31, 2024, 2023 and 2022 respectively. ​ Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows for operating leases ​ $ 3,668 ​ $ 3,720 ​ $ 2,880 ​ Operating cash flows for finance leases ​ $ 22 ​ $ 27 ​ $ 73 ​ Financing cash flows for finance leases ​ $ 119 ​ $ 363 ​ $ 840 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease obligations: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ $ 1,080 ​ $ 2,596 ​ $ 1,315 ​ ​ Supplemental balance sheet information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Finance leases: ​ ​ ​ ​ ​ ​ ​ Property and equipment finance lease assets, gross ​ $ 1,085 ​ $ 1,085 ​ Accumulated depreciation ​ (602) ​ (507) ​ Property and equipment finance lease assets, net ​ $ 483 ​ $ 578 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ Weighted average remaining lease term ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 14.8 years ​ ​ 11.7 years ​ Finance leases ​ ​ 3.0 years ​ ​ 4.0 years ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 6.1 % ​ ​ 6.0 % ​ Finance leases ​ 4.8 % ​ ​ 4.8 % ​ ​ Maturities of lease liabilities as of December 31, 2024 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases Finance leases ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ 2025 ​ $ 2,641 ​ $ 140 ​ 2026 ​ ​ 2,162 ​ ​ 140 ​ 2027 ​ ​ 2,124 ​ ​ 140 ​ 2028 ​ ​ 1,738 ​ ​ — ​ 2029 ​ ​ 1,406 ​ ​ — ​ Thereafter ​ ​ 14,693 ​ ​ — ​ Total lease payments ​ ​ 24,764 ​ ​ 420 ​ Less imputed interest ​ ​ (8,906) ​ ​ (34) ​ Total ​ $ 15,858 ​ $ 386 ​ ​ The current portion of our operating finance Other current liabilities Other liabilities

LONG-TERM DEBT

LONG-TERM DEBT	12 Months Ended
	Dec. 31, 2024
LONG-TERM DEBT
LONG-TERM DEBT	12. LONG-TERM DEBT ​ Long-term debt consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unamortized Discount and ​ ​ ​ Principal ​ Debt Issuance Costs ​ ​ ​ December 31, ​ December 31, ​ ​ 2024 2023 2024 2023 ​ ​ (in thousands) ​ Revolving credit facility ​ $ — ​ $ — ​ $ (7,231) ​ $ (8,118) ​ Term loan ​ 45,703 ​ 60,938 ​ (1,276) ​ (1,416) ​ 8.625% Senior notes due 2029 ​ ​ 400,000 ​ ​ — ​ ​ (8,720) ​ ​ — ​ 7.5% Senior notes due 2025 ​ — ​ 284,607 ​ — ​ (891) ​ Securitization facility ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ June 2020 equipment financing ​ ​ — ​ ​ 2,039 ​ ​ — ​ ​ — ​ February 2024 equipment financing ​ ​ 44,684 ​ ​ — ​ ​ — ​ ​ — ​ ​ ​ 490,387 ​ 347,584 ​ (17,227) ​ (10,425) ​ Less current maturities ​ (26,669) ​ (20,789) ​ 4,394 ​ 451 ​ Total long-term debt ​ $ 463,718 ​ $ 326,795 ​ $ (12,833) ​ $ (9,974) ​ ​ Credit Facility ​ On January 13, 2023, Alliance Coal, as borrower, entered into a Credit Agreement with various financial institutions which was amended on June 12, 2024 (the “Credit Agreement”). The Credit Agreement provides for a $425.0 million revolving credit facility which includes a sublimit of $15.0 million for swingline borrowings and permits the issuance of letters of credit up to the full amount of the Credit Facility (the “Revolving Credit Facility”), and for a term loan in an aggregate principal amount of $75.0 million (the “Term Loan”). The Revolving Credit Facility also includes an incremental facility providing for an increase of $100.0 million at our option subject to lenders agreeing to participate in such incremental facility. The Credit Agreement matures on March 9, 2028, at which time the aggregate outstanding principal amount of all Revolving Credit Facility advances and all Term Loan advances are required to be repaid in full. Interest is payable quarterly, with principal on the Term Loan due in quarterly installments equal to 6.25% of the outstanding balance of the Term Loan on the Credit Agreement amendment date beginning with the quarter ended June 30, 2024. We incurred debt issuance costs during the years ended December 31, 2024 and 2023 of $1.8 million and $12.4 million, respectively, in connection with the Credit Agreement. These debt issuance costs are deferred and amortized as a component of interest expense over the term of the Revolving Credit Facility. ​ The Credit Agreement is guaranteed by ARLP and certain of its subsidiaries, including the Intermediate Partnership and most of the direct and indirect subsidiaries of Alliance Coal (the “Subsidiary Guarantors”). The Credit Agreement also is secured by substantially all of the assets of the Subsidiary Guarantors and Alliance Coal. Borrowings under the Credit Agreement bear interest, at our option, at either (i) an adjusted one-month, three-month or six-month term rate based on the secured overnight financing rate published by the Federal Reserve Bank of New York, plus the applicable margin or (ii) the base rate plus the applicable margin. The base rate is the highest of (i) the Overnight Bank Funding Rate plus 0.50%, (ii) the Administrative Agent’s prime rate, and (iii) the Daily Simple Secured Overnight Financing Rate plus 100 basis points. The applicable margin for borrowings under the Credit Agreement are determined by reference to the Consolidated Debt to Consolidated Cash Flow Ratio. For borrowings under the Term Loan, we elected the one-month term rate, with applicable margin, which was 7.71% as of December 31, 2024. At December 31, 2024, we had $41.0 million of letters of credit outstanding with $384.0 million available for borrowing under the Revolving Credit Facility. We incur an annual commitment fee of 0.50% on the undrawn portion of the Revolving Credit Facility. We utilize the Credit Agreement, as appropriate, for working capital requirements, capital expenditures and investments, scheduled debt payments and distribution payments. ​ The Credit Agreement contains various restrictions affecting Alliance Coal and its subsidiaries, including, among other things, restrictions on incurrence of additional indebtedness and liens, sale of assets, investments, mergers and consolidations and transactions with affiliates. In each case, these restrictions are subject to various exceptions. In addition, restrictions apply to cash distributions by Alliance Coal to the Intermediate Partnership if such distribution would result in exceeding the debt of Alliance Coal to cash flow ratio (as determined in the Credit Agreement) being more than 1.0 to 1.0 or in Alliance Coal having liquidity of less than $200 million. The Credit Agreement requires us to maintain (a) a debt of Alliance Coal to cash flow ratio of not more than 1.5 to 1.0, (b) a consolidated debt of Alliance Coal and the Intermediate Partnership to cash flow ratio of not more than 2.5 to 1.0 and (c) an interest coverage ratio of not less than 3.0 to 1.0, in each case, during the four most recently ended fiscal quarters. The debt of Alliance Coal to cash flow ratio, consolidated debt of Alliance Coal and the Intermediate Partnership to cash flow ratio, and interest coverage ratio were 0.17 to 1.0, 0.91 to 1.0 and 37.97 to 1.0, respectively, for the trailing twelve months ended December 31, 2024. We were in compliance with the covenants of the Credit Agreement as of December 31, 2024 and anticipate remaining in compliance with the covenants. ​ Net restricted assets, as defined by the Securities and Exchange Commission, refers to the amount of our consolidated subsidiaries’ net assets for which the ability to transfer funds to ARLP in the form of cash dividends, loans, advances, or transfers is restricted. As a result of the restrictions contained in the Credit Facility and its associated compliance ratios, the amount of our net restricted assets at December 31, 2024 was $649.2 million. ​ 8.625% Senior Notes due 2029 ​ On June 12, 2024, the Intermediate Partnership and Alliance Resource Finance Corporation (as co-issuer), a wholly owned subsidiary of the Intermediate Partnership (“Alliance Finance”), issued an aggregate principal amount of $400.0 million of senior unsecured notes due 2029 (the “2029 Senior Notes”) in a private placement to qualified institutional buyers. The 2029 Senior Notes have a term of five years, maturing on June 15, 2029 and accrue interest at an annual rate of 8.625%. Interest is payable semi-annually in arrears on each June 15 and December 15. The 2029 Senior Notes are guaranteed, jointly and severally, on a senior unsecured basis by ARLP, certain of ARLP’s wholly owned oil and gas and coal royalties subsidiaries and each of ARLP’s subsidiaries that guarantee obligations under the Credit Agreement. The indenture governing the 2029 Senior Notes contains customary terms, events of default and covenants relating to, among other things, the incurrence of debt, the payment of distributions or similar restricted payments, undertaking transactions with affiliates and limitations on asset sales. ​ At any time prior to June 15, 2026, the issuers may redeem up to 35% of the aggregate principal amount of the 2029 Senior Notes at a redemption price equal to 108.625% of the principal amount redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date, with an amount of cash not greater than the net proceeds from one or more equity offerings. The issuers may also redeem all or a part of the 2029 Senior Notes at any time on or after June 15, 2026, at the redemption prices set forth in the indenture, plus accrued and unpaid interest, if any, to, but excluding, the redemption date. At any time prior to June 15, 2026, the issuers may redeem the 2029 Senior Notes at a redemption price equal to the principal amount plus a “make-whole” premium, plus accrued and unpaid interest, if any, to, but excluding, the redemption date. ​ In addition, if prior to June 15, 2026, a Specified Minerals Disposition (as defined in the indenture governing the 2029 Senior Notes and which involves oil and gas mineral interests) occurs, the issuers will be required to make an offer to purchase up to 40% of the aggregate principal amount of 2029 Senior Notes then outstanding at an offer price in cash in an amount equal to 108.625% of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase. We incurred debt issuance costs during the year ended December 31, 2024 of $9.7 million in connection with the 2029 Senior Notes. These debt issuance costs are deferred and amortized as a component of interest expense over the term of the 2029 Senior Notes. ​ 7.5% Senior Notes due 2025 ​ On April 24, 2017, the Intermediate Partnership and Alliance Finance (as co-issuer) issued an aggregate principal amount of $400.0 million of senior unsecured notes due 2025 in a private placement to qualified institutional buyers. The 7.5% Senior Notes due 2025 had a term of eight years, maturing on May 1, 2025 and accrued interest at an annual rate of 7.5%. In June 2024, we used a portion of the net proceeds from the offering of the 2029 Senior Notes to redeem the outstanding balance of the 7.5% Senior Notes due 2025. ​ Accounts Receivable Securitization ​ Certain direct and indirect wholly owned subsidiaries of our Intermediate Partnership were party to a $90.0 million accounts receivable securitization facility (“Securitization Facility”) that was scheduled to mature in January 2025. Under the Securitization Facility, certain subsidiaries sell certain trade receivables on an ongoing basis to our Intermediate Partnership, which then sells the trade receivables to AROP Funding, LLC (“AROP Funding”), a wholly owned bankruptcy-remote special purpose subsidiary of our Intermediate Partnership, which in turn borrows on a revolving basis up to $90.0 million secured by the trade receivables. After the sale, Alliance Coal, as servicer of the assets, collects the receivables on behalf of AROP Funding. The Securitization Facility bears interest based on a short-term bank yield index. On December 31, 2024, we had $14.8 million of letters of credit outstanding with $73.0 million available for borrowing under the Securitization Facility. The agreement governing the Securitization Facility contains customary terms and conditions, including limitations with regards to certain customer credit ratings. In January 2025, we extended the term of the Securitization Facility to January 2026 and decreased the borrowing availability under the facility up to $75.0 million. At December 31, 2024, we did not have any outstanding borrowings under the Securitization Facility. ​ June 2020 Equipment Financing ​ On June 5, 2020, the Intermediate Partnership entered into an equipment financing arrangement accounted for as debt, wherein the Intermediate Partnership received $14.7 million in exchange for conveying its interest in certain equipment owned indirectly by the Intermediate Partnership and entering into a master lease agreement for that equipment (the “June 2020 Equipment Financing”). The June 2020 Equipment Financing contained customary terms and events of default and provided for forty-eight monthly payments with an implicit interest rate of 6.1%. The June 2020 Equipment Financing matured on June 5, 2024 and the equipment reverted back to the Intermediate Partnership. ​ February 2024 Equipment Financing ​ On February 28, 2024, Alliance Coal entered into an equipment financing arrangement accounted for as debt, wherein Alliance Coal received $54.6 million in exchange for conveying its interest in certain equipment owned indirectly by Alliance Coal and entering into a master lease agreement for that equipment (the “February 2024 Equipment Financing”). The February 2024 Equipment Financing contains customary terms and events of default and provides for forty-eight monthly payments with an implicit interest rate of 8.29%, maturing on February 28, 2028. Upon maturity, the equipment will revert to Alliance Coal. ​ Other ​ We also have an agreement with a bank to provide additional letters of credit in an amount of $5.0 million to maintain surety bonds to secure certain asset retirement obligations and our obligations for workers’ compensation benefits. At December 31, 2024, we had $5.0 million in letters of credit outstanding under this agreement. ​ Aggregate maturities of long-term debt are payable as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) 2025 ​ $ 26,669 ​ 2026 ​ 28,303 ​ 2027 ​ 29,245 ​ 2028 ​ 6,170 ​ 2029 ​ 400,000 ​ ​ ​ $ 490,387 ​ ​

ACCRUED WORKERS' COMPENSATION A

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS	12 Months Ended
	Dec. 31, 2024
ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS
ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS	13. ACCRUED WORKERS’ COMPENSATION AND PNEUMOCONIOSIS BENEFITS ​ The following is a reconciliation of the changes in workers’ compensation liability (including current and long-term liability balances): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 47,975 ​ $ 49,452 ​ Changes in accruals ​ 13,236 ​ 12,155 ​ Payments ​ (14,473) ​ (14,438) ​ Interest accretion ​ 2,037 ​ 2,202 ​ Valuation gain ​ (905) ​ (1,396) ​ Ending balance ​ $ 47,870 ​ $ 47,975 ​ ​ The discount rate used to calculate the estimated present value of future obligations for workers’ compensation was 5.17% and 4.66% at December 31, 2024 and 2023, respectively. ​ The valuation gain in 2024 was primarily attributable to a favorable change in claims development and an increase in the discount rate used to calculate the estimated present value of the future obligations. The valuation gain in 2023 was primarily attributable to a favorable change in claims development partially offset by a decrease in the discount rate used to calculate the estimated present value of the future obligations. ​ As of December 31, 2024 and 2023, we had $106.8 million and $99.4 million, respectively, in surety bonds and letters of credit outstanding to secure workers’ compensation obligations. ​ We limit our exposure to traumatic injury claims by purchasing a high deductible insurance policy that starts paying benefits after deductibles for the particular claim year have been met. Our workers’ compensation liability above is presented on a gross basis and does not include our expected receivables on our insurance policy. Our receivables for traumatic injury claims under this policy as of December 31, 2024 and 2023 were $3.7 million and $4.1 million, respectively. Our receivables are included in Other long-term assets ​ The following is a reconciliation of the changes in pneumoconiosis benefit obligations: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligations at beginning of year ​ $ 132,444 ​ $ 104,287 ​ Service cost ​ 3,443 ​ 2,698 ​ Interest cost ​ 6,231 ​ 4,951 ​ Actuarial loss (gain) ​ (13,990) ​ 25,615 ​ Benefits and expenses paid ​ (3,831) ​ (5,107) ​ Benefit obligations at end of year ​ $ 124,297 ​ $ 132,444 ​ ​ The following is a reconciliation of the changes in the pneumoconiosis benefit obligation recognized in accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial gain (loss) ​ $ 13,990 ​ $ (25,615) ​ $ 9,840 ​ Reversal of amortization item: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ 3,356 ​ 1,382 ​ 1,038 ​ Total recognized in accumulated other comprehensive loss ​ $ 17,346 ​ $ (24,233) ​ $ 10,878 ​ ​ The discount rate used to calculate the estimated present value of future obligations for pneumoconiosis benefits was 5.51%, 4.81% and 5.0% at December 31, 2024, 2023 and 2022, respectively. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ Amount recognized in accumulated other comprehensive loss consists of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ $ 32,399 ​ $ 49,745 ​ $ 25,510 ​ ​ The actuarial gain component of the change in benefit obligations in 2024 was primarily attributable to a) favorable changes in the discount rate, b) favorable demographics in the at-risk population, and c) favorable assumption changes related to Federal and State benefit levels. These favorable changes were partially offset by unfavorable assumption changes regarding future average medical benefits and adjustment based on new hires or re-hires. The actuarial loss component of the change in benefit obligations in 2023 was primarily attributable to a) unfavorable changes in the discount rate, b) unfavorable demographics in the at-risk population, c) unfavorable black lung claims experience, d) unfavorable assumption changes regarding future average medical benefits, and e) unfavorable assumption changes related to Federal and State benefit levels. ​ Summarized below is information about the amounts recognized in the accompanying consolidated balance sheets for pneumoconiosis and workers’ compensation benefits: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Workers’ compensation claims ​ $ 47,870 ​ $ 47,975 ​ Pneumoconiosis benefit claims ​ ​ 124,297 ​ ​ 132,444 ​ Total obligations ​ 172,167 ​ 180,419 ​ Less current portion ​ (14,838) ​ (15,913) ​ Non-current obligations ​ $ 157,329 ​ $ 164,506 ​ ​ Both the pneumoconiosis benefit and workers’ compensation obligations were unfunded at December 31, 2024 and 2023. ​ The pneumoconiosis benefit and workers’ compensation expense consists of the following components: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Service cost $ 3,443 ​ $ 2,698 ​ $ 3,798 ​ Interest cost (1) ​ 6,231 ​ 4,951 ​ 2,991 ​ Net amortization (1) ​ 3,356 ​ 1,382 ​ 1,038 ​ Total pneumoconiosis expense ​ 13,030 ​ 9,031 ​ 7,827 ​ Workers' compensation expense ​ 18,155 ​ 15,152 ​ 11,675 ​ Net periodic benefit cost ​ $ 31,185 ​ $ 24,183 ​ $ 19,502 ​ ________________________________________ (1) Interest cost and net amortization is included in the Other income line item within our consolidated statements of income .

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2024
EMPLOYEE BENEFIT PLANS
EMPLOYEE BENEFIT PLANS	14. EMPLOYEE BENEFIT PLANS ​ Defined Contribution Plans ​ All regular full-time employees are eligible to participate in a defined contribution profit sharing and savings plan (“PSSP”) that we sponsor. PSSP participants may elect to make voluntary contributions to this plan up to a specified amount of their compensation. We make matching contributions based on a percent of an employee’s eligible compensation and also make an additional non-matching contribution. Our contribution expense for the PSSP was approximately $25.5 million, $21.8 million and $19.4 million for the years ended December 31, 2024, 2023 and 2022, respectively. ​ Defined Benefit Plan ​ Eligible employees and former employees of certain of our mining operations participate in a defined benefit plan (the “Pension Plan”) that we sponsor. The Pension Plan is closed to new applicants. Participants in the Pension Plan are no longer receiving benefit accruals for service. The benefit formula for the Pension Plan is a fixed-dollar unit based on years of service. ​ The following sets forth changes in benefit obligations and plan assets for the years ended December 31, 2024 and 2023 and the funded status of the Pension Plan reconciled with the amounts reported in our consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ (dollars in thousands) ​ Change in benefit obligations: ​ ​ ​ ​ ​ ​ ​ Benefit obligations at beginning of year ​ $ 105,870 ​ $ 104,682 ​ Interest cost ​ 5,107 ​ 5,180 ​ Actuarial loss (gain) ​ (4,509) ​ 2,446 ​ Benefits paid ​ (7,491) ​ (6,438) ​ Benefit obligations at end of year ​ 98,977 ​ 105,870 ​ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ 97,252 ​ 92,129 ​ Employer contribution ​ 152 ​ — ​ Actual return on plan assets ​ 11,029 ​ 11,561 ​ Benefits paid ​ (7,491) ​ (6,438) ​ Fair value of plan assets at end of year ​ 100,942 ​ 97,252 ​ Funded status at the end of year ​ $ 1,965 ​ $ (8,618) ​ ​ ​ ​ ​ ​ ​ ​ ​ Amounts recognized in balance sheet: ​ ​ ​ ​ ​ ​ ​ Non-current assets ​ $ 1,965 ​ $ — ​ Non-current liabilities ​ $ — ​ $ (8,618) ​ ​ ​ ​ ​ ​ ​ ​ ​ Amounts recognized in accumulated other comprehensive income consists of: ​ ​ ​ ​ ​ ​ ​ Prior service cost ​ $ (10) ​ $ (196) ​ Net actuarial loss ​ ​ (2,694) ​ ​ (11,584) ​ ​ ​ $ (2,704) ​ $ (11,780) ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average assumption to determine benefit obligations as of December 31, ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 5.51% ​ 4.90% ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average assumptions used to determine net periodic benefit cost for the year ended December 31, ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 4.90% ​ 5.10% ​ Expected return on plan assets ​ 7.50% ​ 7.00% ​ ​ The actuarial gain component of the change in benefit obligations in 2024 was primarily attributable to an increase in the discount rate compared to the prior year end. The actuarial loss component of the change in benefit obligations in 2023 was primarily attributable to a decrease in the discount rate compared to the prior year end. ​ The expected long-term rate of return used to determine our pension liability is based on an asset allocation assumption of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset allocation ​ As of December 31, 2024 assumption Equity securities ​ 75% ​ Fixed income securities 25% ​ ​ 100% ​ ​ The actual return on plan assets was 11.3% and 12.5% for the years ended December 31, 2024 and 2023, respectively. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ ​ (in thousands) Components of net periodic benefit credit: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest cost ​ $ 5,107 ​ $ 5,180 ​ $ 3,749 ​ Expected return on plan assets ​ (7,031) ​ (6,220) ​ (6,638) ​ Amortization of prior service cost ​ ​ 186 ​ ​ 186 ​ ​ 186 ​ Amortization of net loss ​ 383 ​ 682 ​ 1,963 ​ Net periodic benefit credit (1) ​ $ (1,355) ​ $ (172) ​ $ (740) ​ (1) Nonservice components of net periodic benefit credit are included in the Other income (expense) line item within our consolidated statements of income. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Other changes in plan assets and benefit obligation recognized in accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ Net actuarial gain ​ $ 8,507 ​ $ 2,894 ​ Reversal of amortization item: ​ ​ ​ ​ ​ ​ ​ Prior service cost ​ ​ 186 ​ ​ 186 ​ Net actuarial loss ​ 383 ​ 682 ​ Total recognized in accumulated other comprehensive loss ​ 9,076 ​ 3,762 ​ Net periodic benefit credit ​ 1,355 ​ 172 ​ Total recognized in net periodic benefit credit and accumulated other comprehensive loss ​ $ 10,431 ​ $ 3,934 ​ ​ Estimated future benefit payments as of December 31, 2024 are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) ​ ​ ​ ​ ​ 2025 ​ $ 7,832 ​ 2026 ​ 6,700 ​ 2027 ​ 6,830 ​ 2028 ​ 6,924 ​ 2029 ​ 6,996 ​ 2030-2034 ​ 35,431 ​ ​ ​ $ 70,713 ​ ​ We do not expect to make material contributions to the Pension Plan during 2025. ​ The Compensation Committee has appointed an investment manager with full investment authority with respect to Pension Plan investments subject to investment guidelines and compliance with Employee Retirement Income Security Act of 1974 or other applicable laws. The investment manager employs an asset allocation strategy through investment in certain investment types such as equity securities and fixed income securities. The asset allocation process provides that the total portfolio allocation will be adjusted as the funded ratio of the plan changes and market conditions warrant, consistent with managing risks in accordance with plan objectives and time horizon. As the funded ratio improves, more assets may be allocated to the core fixed income portfolio to reduce volatility. The objective of the allocation policy is to achieve an average annual return greater than the actuarial discount rate over the specified time horizon. General asset allocation guidelines at December 31, 2024 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Percentage of Total Portfolio ​ Minimum Maximum ​ ​ ​ ​ ​ ​ Equity securities ​ 50% ​ 85% ​ Fixed income securities ​ 15% ​ 50% ​ ​ Equity securities include domestic and international common stocks, convertible notes and bonds, convertible preferred stocks, American Depository Receipts of non-U.S. companies and Real Estate Investment Trusts. Fixed income securities include debt securities issued by the federal government as well as state and local governments, banker’s acceptances, repurchase agreements, asset-backed securities, collateralized mortgage-backed securities, corporate debt securities, inflation-index bonds and structured notes. ​ The following information discloses the fair values of our Pension Plan assets by asset category: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 ​ 2023 ​ ​ ​ Level 1 ​ Level 2 ​ Level 3 ​ Total ​ Level 1 ​ Level 2 ​ Level 3 ​ Total ​ ​ ​ (in thousands) Cash and cash equivalents ​ $ 2,243 ​ $ — ​ $ — ​ $ 2,243 ​ $ 1,665 ​ $ — ​ $ — ​ $ 1,665 ​ Equity investments - Individual securities (a): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer discretionary ​ ​ 3,572 ​ ​ — ​ ​ — ​ ​ 3,572 ​ ​ 2,605 ​ ​ — ​ ​ — ​ ​ 2,605 ​ Consumer durables ​ ​ 2,257 ​ ​ — ​ ​ — ​ ​ 2,257 ​ ​ 2,088 ​ ​ — ​ ​ — ​ ​ 2,088 ​ Energy ​ ​ 1,046 ​ ​ — ​ ​ — ​ ​ 1,046 ​ ​ 952 ​ ​ — ​ ​ — ​ ​ 952 ​ Financials ​ ​ 5,302 ​ ​ — ​ ​ — ​ ​ 5,302 ​ ​ 4,852 ​ ​ — ​ ​ — ​ ​ 4,852 ​ Health Care ​ ​ 3,972 ​ ​ — ​ ​ — ​ ​ 3,972 ​ ​ 4,296 ​ ​ — ​ ​ — ​ ​ 4,296 ​ Industrials & materials ​ ​ 4,402 ​ ​ — ​ ​ — ​ ​ 4,402 ​ ​ 4,507 ​ ​ — ​ ​ — ​ ​ 4,507 ​ Information technology & communication ​ ​ 9,052 ​ ​ — ​ ​ — ​ ​ 9,052 ​ ​ 8,102 ​ ​ — ​ ​ — ​ ​ 8,102 ​ Fixed income - Investments (b): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preferred stocks non-convertible ​ ​ 14 ​ ​ — ​ ​ — ​ ​ 14 ​ ​ 37 ​ ​ — ​ ​ — ​ ​ 37 ​ Real return mutual funds ​ ​ 464 ​ ​ — ​ ​ — ​ ​ 464 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ Exchange traded mutual funds ​ ​ 591 ​ ​ — ​ ​ — ​ ​ 591 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ Equity investments - Mutual funds (c): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mid-cap stock funds ​ ​ 11,327 ​ ​ — ​ ​ — ​ ​ 11,327 ​ ​ 11,847 ​ ​ — ​ ​ — ​ ​ 11,847 ​ Small-cap stock funds ​ ​ 3,316 ​ ​ — ​ ​ — ​ ​ 3,316 ​ ​ 4,007 ​ ​ — ​ ​ — ​ ​ 4,007 ​ International stock funds ​ ​ 4,689 ​ ​ — ​ ​ — ​ ​ 4,689 ​ ​ 7,849 ​ ​ — ​ ​ — ​ ​ 7,849 ​ Equity investments - Exchange traded funds (d): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Large-cap blend - S&P 500 index ​ ​ 20,144 ​ ​ — ​ ​ — ​ ​ 20,144 ​ ​ 18,044 ​ ​ — ​ ​ — ​ ​ 18,044 ​ International - Developed markets ​ ​ 3,126 ​ ​ — ​ ​ — ​ ​ 3,126 ​ ​ 3,138 ​ ​ — ​ ​ — ​ ​ 3,138 ​ International - Emerging markets ​ ​ 3,338 ​ ​ — ​ ​ — ​ ​ 3,338 ​ ​ 1,894 ​ ​ — ​ ​ — ​ ​ 1,894 ​ Accrued income (e) ​ ​ — ​ ​ 26 ​ ​ — ​ ​ 26 ​ ​ — ​ ​ 29 ​ ​ — ​ ​ 29 ​ ​ ​ $ 78,855 ​ $ 26 ​ $ — ​ $ 78,881 ​ $ 75,883 ​ $ 29 ​ $ — ​ $ 75,912 ​ Commingled investment funds measured at net asset value (f): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income - Investment grade ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 22,061 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21,340 ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 100,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 97,252 ​ (a) Equity investments - Individual securities include investments in publicly traded common stock and American Depository Receipts. Publicly traded common stocks are traded on a national securities exchange and investments in common stocks are valued using quoted market prices multiplied by the number of shares owned. American Depository Receipts are negotiable securities issued by a bank representing shares in a foreign company and traded on a national securities exchange. (b) Fixed income - investments include investments in preferred stock, mutual funds and exchange traded funds that are traded on a national securities exchange and valued using quoted market prices multiplied by the number of shares owned. (c) Equity investments - Mutual funds are valued daily in actively traded markets. For purposes of calculating the value, portfolio securities and other assets for which market quotes are readily available are valued at market value. Investments initially valued in currencies other than the U.S. dollars are converted to the U.S. dollar using exchange rates obtained from pricing services. (d) Equity investments – Exchange traded funds are funds that own financial assets and trade on exchanges, generally tracking a specific index. Investments in exchange traded funds are valued using a market approach based on the quoted market prices. (e) Accrued income represents dividends or interest declared, but not received, on equity securities owned at December 31, 2024. (f) Investments measured at fair value using the net asset value per share (or its equivalent) have not been classified within the fair value hierarchy. The fair values of all commingled investment funds are determined based on the net asset values per unit of each of the funds. The net asset values per unit represent the aggregate value of the fund’s assets at fair value less liabilities, divided by the number of units outstanding .

ASSET RETIREMENT OBLIGATIONS

ASSET RETIREMENT OBLIGATIONS	12 Months Ended
	Dec. 31, 2024
ASSET RETIREMENT OBLIGATIONS
ASSET RETIREMENT OBLIGATIONS	15. ASSET RETIREMENT OBLIGATIONS ​ The following table presents the activity affecting the asset retirement and mine closing liability: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Beginning balance ​ $ 150,443 ​ $ 149,813 ​ Accretion expense ​ 4,528 ​ 4,433 ​ Payments ​ (1,770) ​ (2,317) ​ Allocation of liability associated with mine development and change in assumptions ​ 5,576 ​ (1,486) ​ Ending balance ​ $ 158,777 ​ $ 150,443 ​ ​ For the year ended December 31, 2024, the allocation of liability associated with mine development and change in assumptions increased by $5.6 million. The increase was largely attributable to higher cost assumptions. ​ For the year ended December 31, 2023, the allocation of liability associated with mine development and change in assumptions decreased by $1.5 million. The decrease was largely attributable to lower cost assumptions. ​ The impact of discounting our estimated cash flows resulted in reducing the accrual for asset retirement obligations by $120.1 million and $116.2 million at December 31, 2024 and 2023, respectively. Estimated payments of asset retirement obligations as of December 31, 2024 are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) ​ ​ ​ ​ ​ 2025 ​ $ 3,621 ​ 2026 ​ 4,763 ​ 2027 ​ 7,043 ​ 2028 ​ 9,312 ​ 2029 ​ 9,584 ​ Thereafter ​ 244,592 ​ Aggregate undiscounted asset retirement obligations ​ 278,915 ​ Less: effect of discounting ​ (120,138) ​ Total asset retirement obligations ​ 158,777 ​ Less: current portion ​ (3,621) ​ Non-current asset retirement obligations ​ $ 155,156 ​ ​ As of December 31, 2024 and 2023, we had approximately $170.1 million and $173.5 million, respectively, in surety bonds outstanding to secure the performance of our reclamation obligations.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2024
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	16. COMMITMENTS AND CONTINGENCIES ​ Commitments ​ We lease buildings and equipment under operating lease agreements that provide for the payment of both minimum and contingent rentals. We also have noncancelable coal mineral reserve and resource leases as discussed in Note 21 – Related-Party Transactions. We have contractual commitments of approximately $140.7 million at December 31, 2024. ​ General Litigation ​ Certain of our subsidiaries are party to litigation in which the plaintiffs allege violations of the Fair Labor Standards Act and state law due to alleged failure to compensate for time “donning” and “doffing” equipment and to account for certain bonuses in the calculation of overtime rates and pay. The plaintiffs in these cases sought class and collective action certification, which we opposed. In April 2024, we entered into a settlement agreement with the plaintiffs pursuant to which we agreed to settle such litigation for $15.3 million. As a result of reaching this settlement, which is subject to and awaiting court approval, we have accrued $15.3 million as of December 31, 2024. Our $15.3 million accrual is included in the Other current liabilities ​ We also have various other lawsuits, claims and regulatory proceedings incidental to our business that are pending against the ARLP Partnership. We record an accrual for a potential loss related to these matters when, in management’s opinion, such loss is probable and reasonably estimable. Based on known facts and circumstances, we believe the ultimate outcome of these outstanding lawsuits, claims and regulatory proceedings will not have a material adverse effect on our financial condition, results of operations or liquidity. However, if the results of these matters are different from management’s current expectations and in amounts greater than our accruals (if any), such matters could have a material adverse effect on our business and operations. ​ Other ​ Effective October 1, 2024, we renewed our property and casualty insurance program through September 30, 2025. Our property insurance was procured from our wholly owned captive insurance company, Wildcat Insurance, LLC (“Wildcat Insurance”). Wildcat Insurance charged certain of our subsidiaries for the premiums on this program and in return purchased reinsurance for the program in the standard market. The maximum limit in the commercial property program is $100.0 million per occurrence, excluding a $1.5 million deductible for property damage, a 75- or 90-day waiting period for underground business interruption depending on the mining complex and an additional $25.0 million overall aggregate deductible. We retained a 2.50% participating interest in our current commercial property insurance program. We can make no assurances that we will not experience significant insurance claims in the future that could have a material adverse effect on our business, financial condition, results of operations and ability to purchase property insurance in the future. Also, exposures exist for which no insurance may be available and for which we have not reserved. In addition, the insurance industry has been subject to efforts by environmental activists to restrict coverages available for fossil-fuel companies.

PARTNERS' CAPITAL

PARTNERS' CAPITAL	12 Months Ended
	Dec. 31, 2024
PARTNERS' CAPITAL.
PARTNERS' CAPITAL	17. PARTNERS’ CAPITAL ​ Distributions ​ Our available cash that is not used for unit repurchases may, at the discretion of our general partner, be distributed within 45 days after the end of each quarter to unitholders of record. Available cash is generally defined in the partnership agreement as all cash and cash equivalents on hand at the end of each quarter less reserves established by MGP in its reasonable discretion for future cash requirements. These reserves are retained to provide for the conduct of our business, the payment of debt principal and interest and to provide funds for future distributions. The following table summarizes the quarterly per unit distribution paid during each quarter of 2022 through 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 First Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.250 ​ Second Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.350 ​ Third Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.400 ​ Fourth Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.500 ​ ​ On January 28, 2025, we declared a quarterly distribution of $0.70 per unit, totaling approximately $89.6 million, on all our common units outstanding, which was paid on February 14, 2025 to all unitholders of record on February 7, 2025. ​ Unit Repurchase Program ​ In January 2023, the board of directors of MGP authorized a $93.5 million increase to the unit repurchase program, which had $6.5 million of available capacity as of December 31, 2022. As a result, we were authorized to repurchase up to a total of $100.0 million of ARLP common units. The program has no time limit and we may repurchase units from time to time in the open market or in other privately negotiated transactions. The unit repurchase program authorization does not obligate us to repurchase any dollar amount or number of units. No units were repurchased during the years ended December 31, 2024 and 2022. During the year ended December 31, 2023, we repurchased and retired 929,842 units at an average unit price of $20.90 for an aggregate purchase price of $19.4 million, leaving $80.6 million remaining under the current authorization. Since inception of the unit repurchase program, we have repurchased and retired 6,390,446 units at an average unit price of $17.67 for an aggregate purchase price of $112.9 million. ​ Other ​ The noncontrolling interest in our consolidated balance sheets represents Bluegrass Minerals’ ownership interest in Cavalier Minerals. Our accumulated other comprehensive loss consists of unrecognized actuarial gains and losses as well as unrecognized prior service costs related to our pension and pneumoconiosis benefits. See Note 3 – Variable Interest Entities, Note 13 – Accrued Workers’ Compensation and Pneumoconiosis Benefits and Note 14 – Employee Benefit Plans for further information.

COMMON UNIT-BASED COMPENSATION

COMMON UNIT-BASED COMPENSATION PLANS	12 Months Ended
	Dec. 31, 2024
COMMON UNIT-BASED COMPENSATION PLANS
COMMON UNIT-BASED COMPENSATION PLANS	18. COMMON UNIT-BASED COMPENSATION PLANS ​ Long-Term Incentive Plan ​ A summary of non-vested LTIP grants of restricted units is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average grant date fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-vested grants at January 1, 2022 ​ 3,130,475 ​ $ 5.59 ​ $ 39,569 ​ Granted (1) ​ 769,907 ​ ​ 14.65 ​ ​ ​ ​ Forfeited ​ (203,249) ​ 6.93 ​ ​ ​ ​ Non-vested grants at December 31, 2022 ​ 3,697,133 ​ ​ 7.40 ​ ​ 75,126 ​ Granted (1) ​ 450,125 ​ ​ 21.54 ​ ​ ​ ​ Vested (2) ​ (1,291,330) ​ 5.02 ​ ​ ​ ​ Forfeited ​ (145,584) ​ 6.86 ​ ​ ​ ​ Non-vested grants at December 31, 2023 ​ 2,710,344 ​ ​ 10.91 ​ ​ 57,405 ​ Granted (1) 455,574 ​ ​ 19.69 ​ ​ ​ ​ Vested (2) (1,582,422) ​ 6.53 ​ ​ ​ ​ Forfeited (124,932) ​ 20.37 ​ ​ ​ ​ Non-vested grants at December 31, 2024 1,458,564 ​ 17.60 ​ ​ 38,346 ​ (1) Restricted units granted have certain minimum-value guarantees per unit, regardless of whether the awards vest . (2) During the years ended December 31, 2024 and 2023, we issued 936,544 and 860,060 unrestricted common units, respectively, to the LTIP participants. The remaining vested units were settled in cash to satisfy tax withholding obligations. ​ For the years ended December 31, 2024, 2023 and 2022, our LTIP expense for grants of restricted units was $8.3 million, $10.4 million and $9.4 million, respectively. The total obligation associated with LTIP grants of restricted units as of December 31, 2024 and 2023 was $16.9 million and $19.5 million, respectively, and is included in the partners’ capital Limited partners-common unitholders ​ On January 28, 2025, the Compensation Committee authorized additional grants of 354,261 restricted units, of which 341,137 units were granted. These restricted units have certain minimum-value guarantees, regardless of whether the awards vest. ​ Supplemental Executive Retirement Plan and Directors’ Deferred Compensation Plan ​ A summary of SERP and Directors’ Deferred Compensation Plan activity is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Phantom units outstanding as of January 1, 2022 ​ 668,698 ​ $ 20.37 ​ $ 8,452 ​ Granted ​ 73,842 ​ ​ 19.44 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2022 ​ 742,540 ​ ​ 20.28 ​ ​ 15,088 ​ Granted ​ 118,737 ​ ​ 20.46 ​ ​ ​ ​ Settled (1) ​ (49,331) ​ ​ 20.27 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2023 ​ 811,946 ​ ​ 20.44 ​ ​ 17,197 ​ Granted ​ 100,757 ​ ​ 22.85 ​ ​ ​ ​ Settled (1) (2) (912,703) ​ ​ 26.37 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2024 — ​ ​ ​ ​ ​ ​ (1) During the years ended December 31, 2024 and 2023, we purchased 54,152 and 27,576 ARLP common units, respectively, on the open market to settle the accounts of participants under the SERP. Units purchased were net of units settled in cash to satisfy tax withholding obligations. (2) On December 16, 2024, the SERP and Directors’ Deferred Compensation Plan were terminated, and final distributions of applicable plan accounts were settled in cash. ​ Total SERP and Directors’ Deferred Compensation Plan expense was $2.3 million, $2.4 million and $1.4 million for the years ended December 31, 2024, 2023 and 2022, respectively. As of December 31, 2024, we did not have an obligation associated with the SERP and Directors’ Deferred Compensation Plan as a result of the termination and settlement of the plans in December 2024. As of December 31, 2023, the total obligation associated with the SERP and Directors’ Deferred Compensation Plan was $16.6 million and is included in the partners’ capital Limited partners-common unitholders

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	12 Months Ended
	Dec. 31, 2024
REVENUE FROM CONTRACTS WITH CUSTOMERS
REVENUE FROM CONTRACTS WITH CUSTOMERS	19. REVENUE FROM CONTRACTS WITH CUSTOMERS ​ The following table illustrates the disaggregation of our revenues by type, including a reconciliation to our segment presentation as presented in Note 25 – Segment Information. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ Other, ​ ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ Corporate and ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal Elimination Consolidated ​ ​ ​ (in thousands) ​ Year Ended December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,399,100 ​ $ 712,703 ​ $ — ​ $ — ​ $ — ​ $ 2,111,803 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 138,311 ​ ​ — ​ ​ — ​ ​ 138,311 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 69,676 ​ ​ (69,676) ​ ​ — ​ Transportation revenues ​ ​ 85,142 ​ ​ 27,448 ​ ​ — ​ ​ — ​ ​ — ​ ​ 112,590 ​ Other revenues ​ ​ 11,901 ​ ​ 3,091 ​ ​ 825 ​ ​ 65 ​ ​ 70,122 ​ ​ 86,004 ​ Total revenues ​ $ 1,496,143 ​ $ 743,242 ​ $ 139,136 ​ $ 69,741 ​ $ 446 ​ $ 2,448,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,364,901 ​ $ 845,309 ​ $ — ​ $ — ​ $ — ​ $ 2,210,210 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 137,751 ​ ​ — ​ ​ — ​ ​ 137,751 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 65,572 ​ ​ (65,572) ​ ​ — ​ Transportation revenues ​ ​ 106,150 ​ ​ 36,140 ​ ​ — ​ ​ — ​ ​ — ​ ​ 142,290 ​ Other revenues ​ ​ 10,505 ​ ​ 1,885 ​ ​ 3,774 ​ ​ 42 ​ ​ 60,244 ​ ​ 76,450 ​ Total revenues ​ $ 1,481,556 ​ $ 883,334 ​ $ 141,525 ​ $ 65,614 ​ $ (5,328) ​ $ 2,566,701 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,219,943 ​ $ 882,286 ​ $ — ​ $ — ​ $ — ​ $ 2,102,229 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 151,060 ​ ​ — ​ ​ — ​ ​ 151,060 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,624 ​ ​ (60,624) ​ ​ — ​ Transportation revenues ​ ​ 69,541 ​ ​ 44,319 ​ ​ — ​ ​ — ​ ​ — ​ ​ 113,860 ​ Other revenues ​ ​ 6,821 ​ ​ 1,482 ​ ​ 3,837 ​ ​ 56 ​ ​ 40,622 ​ ​ 52,818 ​ Total revenues ​ $ 1,296,305 ​ $ 928,087 ​ $ 154,897 ​ $ 60,680 ​ $ (20,002) ​ $ 2,419,967 ​ ​ The following table illustrates the projected revenue for all current coal supply contracts allocated to performance obligations that are unsatisfied or partially unsatisfied as of December 31, 2024 and disaggregated by segment and contract duration. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2028 and ​ ​ ​ ​ 2025 2026 2027 Thereafter Total ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Illinois Basin Coal Operations coal revenues ​ $ 993,263 ​ $ 634,042 ​ $ 388,356 ​ $ 633,827 ​ $ 2,649,488 ​ Appalachia Coal Operations coal revenues ​ ​ 548,906 ​ ​ 100,010 ​ ​ 30,105 ​ ​ — ​ ​ 679,021 ​ Total coal revenues (1) ​ $ 1,542,169 ​ $ 734,052 ​ $ 418,461 ​ $ 633,827 ​ $ 3,328,509 ​ (1) Coal revenues generally consists of consolidated revenues excluding our Oil & Gas Royalties segment as well as intercompany revenues from our Coal Royalties segment .

CONCENTRATION OF CREDIT RISK AN

CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS	12 Months Ended
	Dec. 31, 2024
CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS
CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS	20. CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS ​ The international coal market has been a part of our business with indirect sales to end-users in Europe, Africa, Asia, North America and South America. Our sales into the international coal market are considered exports and are made through brokered transactions. During the years ended December 31, 2024, 2023 and 2022, export tons represented approximately 17.3%, 15.7% and 12.5% of tons sold, respectively. ​ Because title to our export shipments typically transfers to our brokerage customers at a point that does not necessarily reflect the end-usage point, we attribute export tons to the country with the end-usage point, if known. No individual country was attributed greater than 10% of total domestic and export tons sold during the years ended December 31, 2024, 2023 and 2022. ​ We have significant long-term coal supply agreements, some of which contain prospective price adjustment provisions designed to reflect changes in market conditions, labor and other production costs and, in the infrequent circumstance when the coal is sold other than free on board the mine, changes in transportation rates. A major customer is defined as a customer from which we derive at least 10% of our total revenues, including transportation revenues. Total revenues from major customers are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ Segment 2024 ​ 2023 ​ 2022 ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Customer A Illinois Basin/Appalachia ​ $ 422,936 ​ $ 332,500 ​ $ — ​ Customer B ​ Illinois Basin ​ ​ 270,448 ​ ​ — ​ ​ 328,406 ​ Customer C ​ Illinois Basin ​ ​ 241,800 ​ ​ 253,573 ​ ​ 260,146 ​ Customer D Illinois Basin/Appalachia ​ — ​ ​ — ​ 228,480 ​ ​ Trade accounts receivable from major customers totaled approximately $50.1 million and $54.3 million at December 31, 2024 and 2023, respectively. Our credit loss experience has historically been insignificant. Financial conditions of our customers could result in a material change to our credit loss expense in future periods. The coal supply agreements with Customers A, B and C expire in 2025, 2030 and 2029, respectively.

RELATED-PARTY TRANSACTIONS

RELATED-PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2024
RELATED-PARTY TRANSACTIONS
RELATED-PARTY TRANSACTIONS	21. RELATED-PARTY TRANSACTIONS ​ We have continuing related-party transactions with MGP and its affiliates. The Board of Directors and its conflicts committee (“Conflicts Committee”) review our related-party transactions that involve a potential conflict of interest between our general partner or its affiliates and ARLP or its subsidiaries or any other partner of ARLP to determine that such transactions are fair and reasonable to ARLP. As a result of these reviews, the Board of Directors and the Conflicts Committee approved each of the transactions described below that had such potential conflict of interest as fair and reasonable to ARLP. ​ Affiliate Coal Lease Agreements ​ The following table summarizes advanced royalties outstanding and related payments and recoupments under our affiliate coal lease agreements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WKY CoalPlay ​ ​ ​ ​ ​ ​ ​ Towhead ​ Henderson ​ WKY ​ ​ ​ ​ ​ Craft Foundations ​ Coal ​ Coal ​ CoalPlay ​ ​ ​ ​ ​ ​ ​ Henderson ​ ​ ​ Henderson ​ ​ ​ ​ ​ ​ Tunnel ​ & Union ​ Henderson ​ & Union ​ ​ ​ ​ ​ ​ Ridge ​ Counties, KY ​ County, KY ​ Counties, KY ​ Total ​ ​ ​ Acquired ​ Acquired ​ Acquired ​ Acquired ​ ​ ​ ​ ​ ​ 2005 ​ 2014 ​ 2014 ​ 2015 ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of January 1, 2022 ​ $ 1,500 ​ $ 21,750 ​ $ 17,650 ​ $ 14,713 ​ $ 55,613 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,522 ​ ​ 2,131 ​ ​ 11,250 ​ Recoupment ​ ​ (3,000) ​ ​ (3,255) ​ ​ — ​ ​ — ​ ​ (6,255) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2022 ​ ​ 1,500 ​ ​ 22,092 ​ ​ 20,172 ​ ​ 16,844 ​ ​ 60,608 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,521 ​ ​ 2,131 ​ ​ 11,249 ​ Recoupment ​ ​ (3,000) ​ ​ (4,258) ​ ​ — ​ ​ — ​ ​ (7,258) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2023 ​ ​ 1,500 ​ ​ 21,431 ​ ​ 22,693 ​ ​ 18,975 ​ ​ 64,599 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,521 ​ ​ 2,131 ​ ​ 11,249 ​ Recoupment ​ ​ (3,000) ​ ​ (5,380) ​ ​ (258) ​ ​ (21) ​ ​ (8,659) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2024 ​ $ 1,500 ​ $ 19,648 ​ $ 24,956 ​ $ 21,085 ​ $ 67,189 ​ ​ Craft Foundations ​ In January 2005, we acquired Tunnel Ridge from ARH. In connection with this acquisition, we assumed a coal lease with Alliance Resource GP, LLC, an entity indirectly wholly owned by Mr. Craft and Kathleen S. Craft until it was dissolved in December 2020. In December 2018, the property subject to the lease was transferred to the Joseph W. Craft III Foundation and the Kathleen S. Craft Foundation, which each hold an undivided one half ​ Tunnel Ridge has a surface land lease with an annual payment of $0.2 million, payable in January of each year with the Craft Foundations. ​ WKY CoalPlay ​ In February 2015, WKY CoalPlay, LLC (“WKY CoalPlay”), an entity owned by the Craft Foundations and two limited liability companies owned by irrevocable trusts established by Mr. Craft and his children, entered into a coal lease agreement with Alliance Resource Properties regarding coal mineral resources located in Henderson and Union Counties, Kentucky. The lease has an initial term of 20 years and provides for earned royalty payments to WKY CoalPlay of 4.0% of the coal sales price and annual minimum royalty payments of $2.1 million. All annual minimum royalty payments are recoupable from future earned royalties. ​ In December 2014, WKY CoalPlay’s subsidiaries, Towhead Coal Reserves, LLC and Henderson Coal Reserves, LLC entered into coal lease agreements with Alliance Resource Properties. The leases have initial terms of 20 years and provide for earned royalty payments of 4.0% of the coal sales price and annual minimum royalty payments of $3.6 million and $2.5 million, respectively. All annual minimum royalty payments under each agreement are recoupable from future earned royalties payable under that agreement.

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2024
INCOME TAXES
INCOME TAXES	22. INCOME TAXES ​ Components of income tax expense are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 16,719 ​ $ 15,917 ​ $ 17,572 ​ State ​ 1,403 ​ 1,336 ​ 1,605 ​ ​ ​ 18,122 ​ 17,253 ​ 19,177 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (2,104) ​ (7,235) ​ 33,038 ​ State ​ (81) ​ (1,738) ​ 1,763 ​ ​ ​ (2,185) ​ (8,973) ​ 34,801 ​ Income tax expense ​ $ 15,937 ​ $ 8,280 ​ $ 53,978 ​ ​ Alliance Minerals’ Tax Election resulted in the recognition of an initial deferred tax liability of $37.3 million with a corresponding increase to income tax expense and reduction of net income for the year ended December 31, 2022. Recognition of the initial deferred tax liability and expense is primarily the result of the $177.0 million non-cash acquisition gain recognized in 2019 related to the acquisition of the remaining interests in AllDale I & II (the “Acquisition Gain”). The Acquisition Gain was recognized to step up to fair value the financial reporting basis of the interests we already owned at the time of acquisition. The tax basis of the underlying properties of AllDale I & II did not include the Acquisition Gain. ​ Reconciliations of income taxes at the U.S. federal statutory tax rate to income taxes at our effective tax rate are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Income taxes at statutory rate ​ $ 80,114 ​ $ 135,335 ​ $ 134,849 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Income taxes at statutory rate on Partnership income not subject to income taxes ​ (61,619) ​ (119,556) ​ (113,925) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Increase (decrease) resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State taxes, net of federal income tax ​ 1,187 ​ 864 ​ 1,492 ​ Change in valuation allowance of deferred tax assets ​ — ​ — ​ (317) ​ Deferred taxes related to tax election ​ ​ — ​ ​ — ​ ​ 37,253 ​ Tax effect of noncontrolling interest income not subject to income taxes ​ ​ (1,058) ​ ​ (1,361) ​ ​ (5,399) ​ Return to accrual adjustments ​ ​ (3,018) ​ ​ (7,008) ​ ​ 69 ​ Other ​ 331 ​ 6 ​ (44) ​ Income tax expense ​ $ 15,937 ​ $ 8,280 ​ $ 53,978 ​ ​ The effective income tax rates for our income tax expense for the years ended December 31, 2024 and 2023 are less than the federal statutory rate, primarily due to the portion of income not subject to income taxes. The effective income tax rate for our income tax expense for the year ended December 31, 2022 is less than the federal statutory rate, primarily due to the portion of income not subject to income taxes, partially offset by the effect of the Tax Election previously discussed. ​ Significant components of deferred tax liabilities and deferred tax assets are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 ​ ​ (in thousands) ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Property, plant and equipment ​ $ (33,168) ​ $ (36,453) ​ Digital assets ​ ​ (4,319) ​ ​ — ​ Other ​ ​ (1,268) ​ ​ — ​ Total deferred tax liabilities ​ ​ (38,755) ​ ​ (36,453) ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred tax assets: ​ ​ ​ ​ ​ ​ ​ Federal loss carryovers and credits ​ ​ 9,016 ​ ​ 4,508 ​ State loss carryovers and credits ​ ​ 3,122 ​ ​ 2,126 ​ Capitalized research and development ​ ​ 2,646 ​ ​ 2,567 ​ Other ​ 2 ​ 1,098 ​ Total deferred tax assets ​ ​ 14,786 ​ ​ 10,299 ​ ​ ​ ​ ​ ​ ​ ​ ​ Overall net deferred tax liabilities ​ $ (23,969) ​ $ (26,154) ​ ​ Deferred tax liabilities for property, plant and equipment are primarily the result of the Alliance Minerals’ Tax Election and associated impact of the Acquisition Gain discussed above. Deferred tax liabilities for digital assets are due to the remeasurement of our digital assets to fair value, which is not taxable until the digital asset is sold. ​ Federal and state loss carryovers and credits are primarily due to net operating losses and research and development credits associated with the operations of other subsidiaries that are taxable for federal income tax purposes. Research and development expenses are required to be capitalized and amortized for U.S. tax purposes, resulting in a deferred tax asset. These expenses are primarily associated with the operations of other subsidiaries that are taxable for federal income tax purposes. Deferred tax assets for federal loss carryovers and credits generally do not have an expiration date. Deferred tax assets for state loss carryovers and credits generally expire between 2027 and 2044 with some carryovers having indefinite carryforward periods. ​ Our 2020 through 2023 tax years remain open to examination by tax authorities, and lower-tier partnership income tax returns for the tax years ended December 31, 2020 and 2021 are being audited by the Internal Revenue Service.

EARNINGS PER LIMITED PARTNER UN

EARNINGS PER LIMITED PARTNER UNIT	12 Months Ended
	Dec. 31, 2024
EARNINGS PER LIMITED PARTNER UNIT
EARNINGS PER LIMITED PARTNER UNIT	23. EARNINGS PER LIMITED PARTNER UNIT ​ We utilize the two-class method in calculating basic and diluted earnings per limited partner unit (“EPU”). Subsequent to the JC Resources Acquisition, net income attributable to ARLP is allocated to limited partners and participating securities with nonforfeitable distributions or distribution equivalents, while net losses attributable to ARLP are allocated only to limited partners but not to participating securities. Prior to the JC Resources Acquisition, in addition to limited partners and participating securities allocations, amounts were also allocated to our general partner for historical earnings from the mineral interests acquired in the JC Resources Acquisition. Our participating securities are outstanding restricted unit awards under our LTIP and phantom units in notional accounts under our SERP and the Directors’ Deferred Compensation Plan. The SERP and Directors’ Deferred Compensation Plan was terminated in December 2024 and will subsequently no longer receive an allocation of income. ​ The following is a reconciliation of net income attributable to ARLP used for calculating basic and diluted earnings per unit and the weighted-average units used in computing EPU. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands, except per unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP ​ $ 360,855 ​ $ 630,118 ​ $ 586,200 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 and diluted ​ 127,965 ​ 127,180 ​ 127,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per limited partner unit - basic and diluted (1) ​ $ 2.77 ​ $ 4.81 ​ $ 4.39 ​ (1) Diluted EPU gives effect to all potentially dilutive common units outstanding during the period using the treasury stock method. Diluted EPU excludes all potentially dilutive units calculated under the treasury stock method if their effect is anti-dilutive. For the years ended December 31, 2024, 2023 and 2022, the combined total of LTIP, SERP and Directors’ Deferred Compensation Plan units of 1,889 , 2,922 and 3,540 , respectively, were considered anti-dilutive under the treasury stock method.

SUPPLEMENTAL CASH FLOW INFORMAT

SUPPLEMENTAL CASH FLOW INFORMATION	12 Months Ended
	Dec. 31, 2024
SUPPLEMENTAL CASH FLOW INFORMATION
SUPPLEMENTAL CASH FLOW INFORMATION	24. SUPPLEMENTAL CASH FLOW INFORMATION ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Cash Paid For: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest ​ $ 44,834 ​ $ 37,126 ​ $ 34,844 ​ Income taxes ​ $ 19,540 ​ $ 13,615 ​ $ 23,794 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-Cash Activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts payable for purchase of property, plant and equipment ​ $ 23,728 ​ $ 14,586 ​ $ 44,281 ​ Right-of-use assets acquired by operating lease ​ $ 1,080 ​ $ 2,596 ​ $ 1,315 ​ Market value of common units distributed under deferred compensation plans before tax withholding requirements ​ $ 34,880 ​ $ 28,906 ​ $ — ​ ​

SEGMENT INFORMATION

SEGMENT INFORMATION	12 Months Ended
	Dec. 31, 2024
SEGMENT INFORMATION
SEGMENT INFORMATION	25. SEGMENT INFORMATION ​ We operate in the United States as a diversified natural resource company that generates operating and royalty income from the production and marketing of coal to major domestic and international utilities and industrial users as well as royalty income from oil & gas mineral interests. We aggregate multiple operating segments into four reportable segments, Illinois Basin Coal Operations, Appalachia Coal Operations, Oil & Gas Royalties and Coal Royalties. We also have an “all other” category referred to as Other, Corporate and Elimination. Our two coal operations reportable segments correspond to major coal producing regions in the eastern United States with similar economic characteristics including coal quality, geology, coal marketing opportunities, mining and transportation methods and regulatory issues. The two coal operations reportable segments include seven mining complexes operating in Illinois, Indiana, Kentucky, Maryland, Pennsylvania, and West Virginia and a coal loading terminal in Indiana on the Ohio River. Our Oil & Gas Royalties reportable segment includes our oil & gas mineral interests which are located primarily in the Permian (Delaware and Midland), Anadarko (SCOOP/STACK) and Williston (Bakken) basins. The operations within our Oil & Gas Royalties reportable segment primarily include receiving royalties and lease bonuses for our oil & gas mineral interests. Our Coal Royalties reportable segment includes coal mineral reserves and resources owned or leased by Alliance Resource Properties, which are either (a) leased to our mining complexes or (b) near our coal mining operations but not yet leased. ​ The Illinois Basin Coal Operations reportable segment includes (a) the Gibson County Coal, LLC’s mining complex, (b) the Warrior Coal, LLC mining complex, (c) the River View mining complex and (d) the Hamilton mining complex. The segment also includes our Mt. Vernon Transfer Terminal, LLC coal loading terminal in Indiana which operates on the Ohio River, Mid-America Carbonates, LLC and other support services, and our non-operating mining complexes. ​ The Appalachia Coal Operations reportable segment includes (a) the Mettiki mining complex, (b) the Tunnel Ridge mining complex and (c) the MC Mining mining complex. ​ The Oil & Gas Royalties reportable segment includes oil & gas mineral interests held by Alliance Minerals’ through its consolidated subsidiaries as well as equity interests held in AllDale III (Note 3 – Variable Interest Entities). ​ Coal Royalties reportable segment includes coal mineral reserves and resources owned or leased by Alliance Resource Properties that are (a) leased to certain of our mining complexes in both the Illinois Basin Coal Operations and Appalachia Coal Operations reportable segments or (b) located near our operations and external mining operations. Approximately 63% of the coal sold by our coal operations’ mines is leased from our Coal Royalties entities. ​ Other, Corporate and Elimination includes marketing and administrative activities, the Matrix Group, Bitiki, which holds our crypto-mining activities (see Note 7 – Digital Assets), our investments in Francis, Infinitum, NGP ET IV and Ascend (see Note 3 – Variable Interest Entities and Note 10 – Equity Investments), Wildcat Insurance, which assists the ARLP Partnership with its insurance requirements, and AROP Funding and Alliance Finance (both discussed in Note 12 – Long-Term Debt). The eliminations included in Other, Corporate and Elimination primarily represent the intercompany coal royalty transactions described above between our Coal Royalties reportable segment and our coal operations’ mines. ​ Reportable segment results are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal Total ​ ​ (in thousands) Year Ended December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,496,143 ​ $ 743,242 ​ $ 139,136 ​ $ 65 ​ $ 2,378,586 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 69,676 ​ ​ 69,676 ​ Total revenues (1) ​ ​ 1,496,143 ​ ​ 743,242 ​ ​ 139,136 ​ ​ 69,741 ​ ​ 2,448,262 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 937,083 ​ ​ 551,734 ​ ​ 19,853 ​ ​ 25,759 ​ 1,534,429 ​ Transportation expenses ​ ​ 85,142 ​ ​ 27,448 ​ ​ — ​ ​ — ​ ​ 112,590 ​ Other segment items (3) ​ ​ — ​ ​ — ​ ​ 2,325 ​ ​ — ​ ​ 2,325 ​ Segment Adjusted EBITDA (4) ​ 473,918 ​ ​ 164,060 ​ ​ 116,958 ​ ​ 43,982 ​ 798,918 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 1,028,622 ​ ​ 467,463 ​ ​ 818,502 ​ ​ 307,924 ​ 2,622,511 ​ Capital expenditures (6) ​ 301,591 ​ ​ 109,315 ​ ​ — ​ ​ — ​ 410,906 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,481,556 ​ $ 883,334 ​ $ 141,525 ​ $ 42 ​ $ 2,506,457 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 65,572 ​ ​ 65,572 ​ Total revenues (1) ​ ​ 1,481,556 ​ ​ 883,334 ​ ​ 141,525 ​ ​ 65,614 ​ ​ 2,572,029 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 861,288 ​ ​ 516,471 ​ ​ 16,532 ​ ​ 24,451 ​ 1,418,742 ​ Transportation expenses ​ ​ 106,150 ​ ​ 36,140 ​ ​ — ​ ​ — ​ ​ 142,290 ​ Other segment items (3) ​ ​ — ​ ​ — ​ ​ 3,485 ​ ​ — ​ ​ 3,485 ​ Segment Adjusted EBITDA (4) ​ 514,118 ​ ​ 330,723 ​ ​ 121,508 ​ ​ 41,163 ​ 1,007,512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 966,102 ​ ​ 488,427 ​ ​ 781,184 ​ ​ 315,592 ​ 2,551,305 ​ Capital expenditures (6) ​ 257,885 ​ ​ 116,217 ​ ​ — ​ ​ 400 ​ 374,502 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,296,305 ​ $ 928,087 ​ $ 154,897 ​ $ 56 ​ $ 2,379,345 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,624 ​ ​ 60,624 ​ Total revenues (1) ​ ​ 1,296,305 ​ ​ 928,087 ​ ​ 154,897 ​ ​ 60,680 ​ ​ 2,439,969 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 806,080 ​ 464,029 ​ 15,395 ​ 21,871 ​ 1,307,375 ​ Transportation expenses ​ ​ 69,541 ​ ​ 44,319 ​ ​ — ​ ​ — ​ ​ 113,860 ​ Other segment items (3) ​ ​ — ​ ​ (6,663) ​ ​ (3,677) ​ ​ — ​ ​ (10,340) ​ Segment Adjusted EBITDA (4) ​ 420,684 ​ 426,402 ​ 143,179 ​ 38,809 ​ 1,029,074 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 779,018 ​ 431,913 ​ 778,465 ​ 321,587 ​ 2,310,983 ​ Capital expenditures (6) ​ 158,624 ​ 76,603 ​ — ​ 38,276 ​ 273,503 ​ (1) The following is a reconciliation of our total segment revenues to total consolidated revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment revenues ​ $ 2,448,262 ​ $ 2,572,029 ​ $ 2,439,969 ​ Other, Corporate and Elimination revenues - Outside ​ ​ 70,122 ​ ​ 60,244 ​ ​ 40,622 ​ Other, Corporate and Elimination revenues - Intercompany ​ ​ (69,676) ​ ​ (65,572) ​ ​ (60,624) ​ Total consolidated revenues ​ $ 2,448,708 ​ $ 2,566,701 ​ $ 2,419,967 ​ ​ Revenues included in Other, Corporate and Elimination are attributable to intercompany eliminations, which are primarily intercompany coal royalties eliminations, outside revenues at the Matrix Group and other outside miscellaneous sales and revenue activities. ​ (2) Segment Adjusted EBITDA Expense includes operating expenses, coal purchases, if applicable, and other income or expense as adjusted to remove certain items from operating expenses that we characterize as unrepresentative of our ongoing operations such as certain litigation accruals. Segment Adjusted EBITDA Expense is used as a financial measure by our management to assess the operating performance of our segments. Segment Adjusted EBITDA Expense is a key component of Segment Adjusted EBITDA in addition to coal sales, royalty revenues and other revenues. The exclusion of corporate general and administrative expenses from Segment Adjusted EBITDA Expense allows management to focus solely on the evaluation of segment operating performance as it primarily relates to our operating expenses. ​ (3) Other segment items for each reportable segment includes: Appalachia Coal Operations Oil & Gas Royalties ​ (4) Segment Adjusted EBITDA is defined as net income attributable to ARLP before net interest expense, income taxes, depreciation, depletion and amortization and general and administrative expenses modified for certain items that we characterize as unrepresentative of our ongoing operations, such as the change in fair value of digital assets and certain litigation accruals. Segment Adjusted EBITDA is used as a financial measure by Mr. Craft, the Chairman, President and Chief Executive Officer of MGP, who is also our chief operating decision maker (“CODM”), other management and by external users of our financial statements such as investors, commercial banks, research analysts and others. Our CODM uses Segment Adjusted EBITDA in assessing segment performance and deciding how to allocate resources. Segment Adjusted EBITDA provides useful information to our CODM and investors regarding our performance and results of operations because Segment Adjusted EBITDA (i) provides additional information about our core operating performance and ability to generate and distribute cash flow, (ii) provides investors with the financial analytical framework upon which we base financial, operational, compensation and planning decisions, (iii) presents a measurement that investors, rating agencies and debt holders have indicated is useful in assessing us and our results of operations and (iv) allows our CODM and management to focus solely on the evaluation of segment operating profitability as it relates to our revenues and operating expenses, which are primarily controlled by our segments. ​ The following is a reconciliation of total Segment Adjusted EBITDA for our segments to consolidated income before income taxes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Segment Adjusted EBITDA – total segments ​ $ 798,918 ​ $ 1,007,512 ​ $ 1,029,074 ​ Other, Corporate and Elimination profit (loss) ​ (2,464) ​ 4,661 ​ 3,495 ​ General and administrative ​ ​ (82,224) ​ ​ (79,096) ​ ​ (80,425) ​ Depreciation, depletion and amortization ​ ​ (285,446) ​ ​ (267,982) ​ ​ (276,670) ​ Asset Impairments ​ ​ (31,130) ​ ​ — ​ ​ — ​ Interest expense, net ​ ​ (28,007) ​ ​ (26,697) ​ ​ (35,296) ​ Change in fair value of digital assets ​ ​ 22,395 ​ ​ — ​ ​ — ​ Litigation expense accrual ​ (15,250) ​ — ​ — ​ Noncontrolling interest ​ ​ 4,702 ​ ​ 6,052 ​ ​ 1,958 ​ Income before income taxes ​ $ 381,494 ​ $ 644,450 ​ $ 642,136 ​ ​ Other, Corporate and Elimination profit (loss) represents profit (loss) from operating segments below the quantitative thresholds when determining our reportable segments as well as the elimination of intersegment profit (loss) between our reportable segments. The operating segments included are those described as part of our Other, Corporate and Eliminations category. ​ (5) The following is a reconciliation of our total segment assets to total consolidated assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment assets ​ $ 2,622,511 ​ $ 2,551,305 ​ $ 2,310,983 ​ Other, Corporate and Elimination total assets ​ ​ 293,219 ​ ​ 237,121 ​ ​ 417,038 ​ Total consolidated assets ​ $ 2,915,730 ​ $ 2,788,426 ​ $ 2,728,021 ​ ​ (6) Capital expenditures shown exclude $24.7 million, $110.9 million and $92.6 million paid for oil & gas acquisitions in 2024, 2023 and 2022, respectively. See Note 4 – Acquisitions for more information. The following is a reconciliation of our total segment capital expenditures to total consolidated capital expenditures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment capital expenditures ​ $ 410,906 ​ $ 374,502 ​ $ 273,503 ​ Other, Corporate and Elimination capital expenditures ​ ​ 17,835 ​ ​ 4,836 ​ ​ 12,891 ​ Total consolidated capital expenditures ​ $ 428,741 ​ $ 379,338 ​ $ 286,394 ​ ​

SUBSEQUENT EVENT

SUBSEQUENT EVENT	12 Months Ended
	Dec. 31, 2024
SUBSEQUENT EVENT
SUBSEQUENT EVENT	26. SUBSEQUENT EVENT ​ In February 2025, we committed to invest up to $25.0 million in a limited partnership sponsored by a private equity firm, which partnership vehicle intends to own, indirectly, an interest in a joint venture holding company formed with a third party that plans to indirectly acquire, own and operate a coal-fired electric generating plant. As of February 27, 2025, we have not funded any portion of our capital commitment.

SCHEDULE I CONDENSED FINANCIAL

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF REGISTRANT	12 Months Ended
	Dec. 31, 2024
CONDENSED FINANCIAL INFORMATION OF REGISTRANT
CONDENSED FINANCIAL INFORMATION OF REGISTRANT	SCHEDULE I – CONDENSED FINANCIAL INFORMATION OF REGISTRANT ALLIANCE RESOURCE PARTNERS, L.P. ​ CONDENSED BALANCE SHEETS (PARENT) DECEMBER 31, 2024 AND 2023 (In thousands, except unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ASSETS ​ ​ ​ ​ ​ CURRENT ASSETS: ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 1,942 ​ $ 2,043 ​ Total current assets ​ 1,942 ​ 2,043 ​ OTHER ASSETS: ​ ​ ​ ​ ​ ​ ​ Investments in consolidated subsidiaries ​ 1,866,102 ​ 1,894,158 ​ Total other assets ​ 1,866,102 ​ 1,894,158 ​ TOTAL ASSETS ​ $ 1,868,044 ​ $ 1,896,201 ​ ​ ​ ​ ​ ​ ​ ​ ​ LIABILITIES AND PARTNERS' CAPITAL ​ ​ ​ ​ ​ ​ ​ CURRENT LIABILITIES: ​ ​ ​ ​ ​ ​ ​ Accrued taxes other than income taxes ​ $ 194 ​ $ 174 ​ Total current liabilities ​ 194 ​ 174 ​ Total liabilities ​ 194 ​ 174 ​ ​ ​ ​ ​ ​ ​ ​ ​ PARTNERS' CAPITAL: ​ ​ ​ ​ ​ ​ ​ Limited Partners - Common Unitholders 128,061,981 and 127,125,437 units outstanding, respectively ​ 1,867,850 ​ 1,896,027 ​ TOTAL LIABILITIES AND PARTNERS' CAPITAL ​ $ 1,868,044 ​ $ 1,896,201 ​ See accompanying notes. ​ CONDENSED STATEMENTS OF OPERATIONS (PARENT) FOR THE YEARS ENDED DECEMBER 31, 2024, 2023 AND 2022 (In thousands, except unit and per unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 EXPENSES: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ General and administrative ​ $ 301 ​ $ 151 ​ $ — ​ Total operating expenses ​ 301 ​ 151 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ LOSS FROM OPERATIONS ​ (301) ​ (151) ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest income ​ ​ 94 ​ ​ 57 ​ ​ — ​ Equity in earnings of consolidated subsidiaries ​ 361,062 ​ 630,212 ​ 586,200 ​ NET INCOME ATTRIBUTABLE TO ARLP ​ $ 360,855 ​ $ 630,118 ​ $ 586,200 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NET INCOME ATTRIBUTABLE TO ARLP ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ GENERAL PARTNER ​ $ — ​ $ 1,384 ​ $ 9,010 ​ LIMITED PARTNERS ​ $ 360,855 ​ $ 628,734 ​ $ 577,190 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ EARNINGS PER LIMITED PARTNER UNIT - BASIC AND DILUTED ​ $ 2.77 ​ $ 4.81 ​ $ 4.39 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING – BASIC AND DILUTED ​ 127,964,744 ​ 127,180,312 ​ 127,195,219 ​ See accompanying notes. ​ CONDENSED STATEMENTS OF CASH FLOWS (PARENT) FOR THE YEARS ENDED DECEMBER 31, 2024, 2023 AND 2022 (In thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ CASH FLOWS FROM OPERATING ACTIVITIES: ​ $ 363,329 ​ $ 364,448 ​ $ 196,348 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ CASH FLOWS FROM FINANCING ACTIVITIES: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Distributions paid to Partners ​ ​ (363,430) ​ (364,579) ​ (196,347) ​ Net cash used in financing activities ​ (363,430) ​ (364,579) ​ (196,347) ​ NET CHANGE IN CASH AND CASH EQUIVALENTS ​ (101) ​ (131) ​ 1 ​ CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD ​ 2,043 ​ 2,174 ​ 2,173 ​ CASH AND CASH EQUIVALENTS AT END OF PERIOD ​ $ 1,942 ​ $ 2,043 ​ $ 2,174 ​ See accompanying notes. ​ ​ NOTES TO FINANCIAL INFORMATION (PARENT) ​ 1. BASIS OF PRESENTATION ​ In these parent-company-only financial statements, our investment in consolidated subsidiaries is stated at cost plus equity in undistributed earnings of subsidiaries and reduced by distributions received from subsidiaries since the date of acquisition. These parent-company-only financial statements should be read in conjunction with our consolidated financial statements in “Item 8. Financial Statements and Supplementary Data” of this Annual Report on Form 10-K. ​ 2. GUARANTEES ​ As the parent of Alliance Coal and the Intermediate Partnership, ARLP is a guarantor of the Credit Facility and the 2029 Senior Notes discussed in “Item 8. Financial Statements and Supplementary Data—Note 12 – Long-Term Debt” of this Annual Report on Form 10-K. In addition to these guarantees, ARLP has provided guarantees on surety indemnity agreements and financially guaranteed certain coal supply agreements. The duration of these guarantees varies. The maximum undiscounted potential future payment obligation for our guarantees of certain coal supply agreements as of December 31, 2024 is approximately $21.9 million. These guarantees provide for compensation to customers based on additional cost to the customer to replace any contracted tons that our subsidiaries fail to deliver. We do not expect to make any payments under these guarantees. ​ 3. CASH DISTRIBUTIONS RECEIVED ​ We received distributions of $363.4 million, $364.6 million and $196.3 million from our consolidated subsidiaries during the years ended December 31, 2024, 2023, and 2022, respectively.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 360,855	$ 630,118	$ 586,200

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Insider Trading Policies and Pr

Insider Trading Policies and Procedures	12 Months Ended
	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Cybersecurity Risk Management a

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
	Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Risk Assessment: ​ Regular assessments are conducted across our systems, networks, and data infrastructure to identify potential cybersecurity threats and vulnerabilities. These assessments include penetration testing, vulnerability scanning, and red teaming exercises conducted by third-party service providers, which help us to evaluate the likelihood and potential impact of cybersecurity incidents. Feedback from these assessments is incorporated into our systems and procedures through upgrades intended to further improve our security posture. ​ Incident Identification and Response: ​ A monitoring and detection system has been implemented to help identify cybersecurity incidents. The IT Security Department is tasked with monitoring certain network activities, logs, and system behavior, leveraging threat detection technologies. In the event of any breach or cybersecurity incident, we have an incident response plan that is designed to follow industry best practices and aligns with legal and regulatory requirements. This plan is designed to provide for immediate action to contain the incident, mitigate the impact, and restore normal operations efficiently. ​ Cybersecurity Training and Awareness: ​ Cybersecurity awareness among our employees is promoted with regular training and awareness programs. Employees receive training on recognizing and reporting potential cybersecurity threats, best practices for data protection, and adhering to cybersecurity policies and procedures. Additionally, periodic simulated phishing exercises are conducted to enhance employee readiness in identifying and mitigating phishing attacks. ​ Access Controls: ​ Access control policies have been implemented to limit unauthorized access to sensitive information and we seek to maintain and monitor critical systems. Multi-factor authentication is used for remote access, use of privileged accounts and access to critical systems. ​ Encryption and Data Protection: ​ Encryption methods are used to protect sensitive data in transit and at rest. This includes the encryption of customer data, financial information, and other confidential data.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	cybersecurity risk management processes are integrated into the Partnership’s overall risk management program. Cybersecurity threats are understood to be dynamic and intersect with various other enterprise risks. As such, cybersecurity is considered an important component of our enterprise-wide risk management approach
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	The Board of Directors oversees risks from cybersecurity threats. Recognizing the importance of cybersecurity to the success and resilience of our business, the Board considers cybersecurity to be an important aspect of corporate governance. To facilitate effective oversight, the Audit Committee and the Board of Directors hold discussions with management, including the CTO on cybersecurity risks, incident trends, and the effectiveness of cybersecurity measures annually and as needed during both scheduled and special meetings. If new material cybersecurity risks arise, the Board of Directors and the Audit Committee are informed through regular discussions between the CFO and both the Chairman of the Board and the Audit Committee Chair. These discussions are then brought to the attention of the Board of Directors and Audit Committee at the next meeting.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Cybersecurity Steering Committee reviews information security policies and cybersecurity risks in conjunction with other operational, financial, and strategic risks to ensure alignment with our business objectives. The Cybersecurity Steering Committee convenes regularly to review and monitor the Partnership’s programs for the prevention, detection, mitigation, and remediation of cybersecurity incidents. The Cybersecurity Steering Committee receives reports on security incidents, threat intelligence, and vulnerability assessments from our IT Security Department.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	To facilitate effective oversight, the Audit Committee and the Board of Directors hold discussions with management, including the CTO on cybersecurity risks, incident trends, and the effectiveness of cybersecurity measures annually and as needed during both scheduled and special meetings. If new material cybersecurity risks arise, the Board of Directors and the Audit Committee are informed through regular discussions between the CFO and both the Chairman of the Board and the Audit Committee Chair. These discussions are then brought to the attention of the Board of Directors and Audit Committee at the next meeting.
Cybersecurity Risk Role of Management [Text Block]	The CTO and the Cybersecurity Steering Committee are responsible for overseeing and executing our cybersecurity strategy, including the assessment and management of cybersecurity risks. The CTO reports directly to the CFO and maintains communication with the Audit Committee, the Board of Directors and the Cybersecurity Steering Committee with respect to information security and cybersecurity matters. ​ The CTO holds a Master of Business Administration from the University of Kentucky/University of Louisville’s joint executive program and has an extensive background in information security, risk management, and incident response with over twenty years of varying information technology roles with increasing responsibility at both private and public companies. The CTO is supported by a dedicated team of cybersecurity professionals, each bringing diverse expertise in areas such as network security, data protection, and threat intelligence.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	The CTO and the Cybersecurity Steering Committee are responsible for overseeing and executing our cybersecurity strategy, including the assessment and management of cybersecurity risks
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	The CTO holds a Master of Business Administration from the University of Kentucky/University of Louisville’s joint executive program and has an extensive background in information security, risk management, and incident response with over twenty years of varying information technology roles with increasing responsibility at both private and public companies
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2024
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Variable Interest Entity ("VIE")	Variable Interest Entity (“VIE”) ​ VIEs are primarily entities that lack sufficient equity to finance their activities without additional financial support from other parties or whose equity holders, as a group, lack one or more of the following characteristics: (a) direct or indirect ability to make decisions, (b) obligation to absorb expected losses or (c) right to receive expected residual returns. A VIE must be evaluated quantitatively and qualitatively to determine the primary beneficiary, which is the reporting entity that has (a) the power to direct activities of a VIE that most significantly impact the VIE’s economic performance and (b) the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. The primary beneficiary is required to consolidate the VIE for financial reporting purposes. ​ To determine a VIE’s primary beneficiary, we perform a qualitative assessment to determine which party, if any, has the power to direct activities of the VIE and the obligation to absorb losses and/or receive its benefits. This assessment involves identifying the activities that most significantly impact the VIE’s economic performance and determine whether it, or another party, has the power to direct those activities. When evaluating whether we are the primary beneficiary of a VIE, we perform a qualitative analysis that considers the design of the VIE, the nature of our involvement and the variable interests held by other parties.
Business Combinations	Business Combinations ​ A business consists of inputs and processes applied to those inputs that have the ability to contribute to the creation of outputs. We account for the acquisition of a business as a business combination, where we record the assets acquired, including identified intangible assets and liabilities assumed at their fair value, which in many instances involves estimates based on third-party valuations, such as appraisals, or internal valuations based on discounted cash flow analyses or other valuation techniques. However, if substantially all the fair value of the assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets with the same risk profile, the acquisition is accounted for as an asset acquisition and recorded at cost.
Estimates	Estimates ​ The preparation of consolidated financial statements in conformity with generally accepted accounting principles of the United States (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts and disclosures in the consolidated financial statements. Actual results could differ from those estimates. Significant estimates and assumptions include: ​ ● Asset retirement obligations; ● Pension obligations; ● Workers’ compensation and pneumoconiosis obligations; ● Acquisition related purchase price allocations; ● Life of mine assumptions; ● Oil & gas reserve quantities and carrying amounts; ● Determination of oil & gas revenue accruals; and ● Contingent consideration liability
Fair Value Measurements	Fair Value Measurements ​ We apply fair value measurements to certain assets and liabilities. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. Fair value is based on assumptions that market participants would use when pricing an asset or liability, including assumptions about risk and risks inherent in valuation techniques and inputs to valuations. Fair value measurements assume that the transaction occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability (the market for which the reporting entity would be able to maximize the amount received or minimize the amount paid). Valuation techniques used in our fair value measurements are based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect our own market assumptions. ​ We use the following fair value hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value into three broad levels: ​ ● Level 1 – Quoted prices for identical assets and liabilities in active markets that we have the ability to access at the measurement date. ​ ● Level 2 – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model derived valuations whose inputs are observable or whose significant value drivers are observable. ​ ● Level 3 – Unobservable inputs for the asset or liability including situations where there is little, if any, market activity for the asset or liability. ​ The fair value hierarchy gives the highest priority to quoted prices in active markets (Level 1) and the lowest priority to unobservable data (Level 3). In some cases, the inputs used to measure fair value might fall into different levels of the fair value hierarchy. The lowest level input that is significant to a fair value measurement determines the applicable level in the fair value hierarchy. Assessing the significance of a particular input to the fair value measurement requires judgment, considering factors specific to the asset or liability. Significant fair value measurements are used in our significant estimates and are discussed throughout these notes.
Cash and Cash Equivalents	Cash and Cash Equivalents ​ Cash and cash equivalents include cash on hand and on deposit, including highly liquid investments with maturities of three months or less. At times the ARLP Partnership maintains deposits in federally insured financial institutions in excess of stated federally insured limits.
Cash Management	Cash Management ​ The cash flows from operating activities section of our consolidated statements of cash flows reflects adjustments of $3.3 million and $6.7 million representing book overdrafts at December 31, 2024 and 2023, respectively. We did not have material book overdrafts at December 31, 2022.
Inventories	Inventories ​ Coal inventories are stated at the lower of cost or net realizable value on a first-in, first-out basis. Supply, finished goods, work in process and raw materials inventories are stated at an average cost basis, less a reserve for obsolete and surplus items.
Advance Royalties	Advance Royalties ​ Rights to coal mineral leases are often acquired and/or maintained through advance royalty payments. Where royalty payments represent prepayments recoupable against future production, they are recorded as an asset, with amounts expected to be recouped within one year classified as a current asset. As mining occurs on these leases, the royalty prepayments are charged to operating expenses. We assess the recoverability of royalty prepayments based on estimated future production. Royalty prepayments estimated to be nonrecoverable are expensed. Our advance royalties are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Advance royalties, affiliates (see Note 21– Related-Party Transactions) ​ $ 67,189 ​ $ 64,599 ​ Advance royalties, third-parties ​ 14,497 ​ 14,306 ​ Total advance royalties ​ $ 81,686 ​ $ 78,905 ​
Digital Assets	Digital Assets ​ We began our crypto-mining activities during the second half of 2020 as we started mining bitcoin as a pilot project to monetize already paid for, yet underutilized, electricity load. We continue to periodically be awarded digital assets through our crypto-mining activities. The awards are accounted for as revenue and valued at the exchange quoted price at the time they are awarded. Beginning January 1, 2024, with our adoption of the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-08, Intangibles - Goodwill and Other - Crypto Assets (Subtopic 350-60) Digital assets Change in fair value of digital assets
Property, Plant and Equipment	Property, Plant and Equipment ​ Expenditures which extend the useful lives of existing plant and equipment assets are capitalized. Interest costs associated with major asset additions are capitalized during the construction period. Maintenance and repairs that do not extend the useful life or increase productivity of the asset are charged to operating expense as incurred. Exploration expenditures are charged to operating expense as incurred, including costs related to drilling and study costs incurred to convert or upgrade mineral resources to reserves. Processing facilities and mineral rights, assuming current production estimates, are depreciated or depleted using the units-of-production method. Mining equipment and other plant and equipment assets are depreciated principally using the straight-line method over the remaining estimated life of each mine. Buildings, office equipment and improvements are amortized straight line over their estimated useful lives. Gains or losses arising from retirements are included in operating expenses. Depletion of coal mineral rights is provided on the basis of tonnage mined in relation to estimated recoverable tonnage, which equals estimated proven and probable coal mineral reserves. Therefore, our coal mineral rights are depleted based on only proven and probable coal mineral reserves. See Oil & Gas Reserve Quantities and Carrying Amounts
Mine Development Costs	Mine Development Costs ​ Mine development costs are capitalized until production, other than production incidental to the mine development process, commences and are amortized on a units of production method based on the estimated proven and probable coal mineral reserves. Mine development costs represent costs incurred in establishing access to coal mineral reserves and include costs associated with sinking or driving shafts and underground drifts, permanent excavations, roads and tunnels. The end of the development phase and the beginning of the production phase takes place when construction of the mine for economic extraction is substantially complete. Coal extracted during the development phase is incidental to the mine’s production capacity and is not considered to shift the mine into the production phase.
Long-Lived Asset Impairment	Long-Lived Asset Impairment ​ We review the carrying value of long-lived assets and certain identifiable intangibles whenever events or changes in circumstances indicate that the carrying amount of an asset group may not be recoverable based on estimated undiscounted future cash flows. To the extent the carrying amount of an asset group is not recoverable based on undiscounted cash flows, the amount of impairment is measured by the difference between the carrying value and the fair value (See Note 9 – Long-Lived Asset Impairments).
Oil & Gas Reserve Quantities and Carrying Amounts	Oil & Gas Reserve Quantities and Carrying Amounts ​ We are wholly dependent on third-party operators to explore, develop, produce and operate the properties associated with our mineral interests. We follow the successful efforts method of accounting for our oil & gas mineral interests. Under this method, costs to acquire mineral interests in oil & gas properties are capitalized when incurred. The costs of mineral interests in unproved properties are capitalized pending the results of exploration and leasing efforts by operators. As mineral interests in unproved properties are determined to be proved, the related costs are transferred to proved oil & gas properties. ​ Mineral interests in oil & gas properties are grouped using a reasonable aggregation of properties with a common geological structural feature or stratigraphic condition, which we may also refer to as a depletable group. Mineral interests in proved oil & gas properties are depleted based on the units-of-production method. Proved reserves are quantities of oil & gas that can be estimated with reasonable certainty to be recoverable in the future from a given date forward, from known reservoirs, under existing economic conditions, operating methods, and government regulations. Proved developed resources are the quantities expected to be recovered through the operators’ existing wells with existing equipment, infrastructure and operating methods. ​ We evaluate impairment of our oil & gas mineral interests in proved properties whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. This evaluation is performed on a depletable group basis. We compare the undiscounted projected future cash flows expected in connection with a depletable group to its unamortized carrying amount to determine recoverability. When the carrying amount of a depletable group exceeds its estimated undiscounted future cash flows, the carrying amount is written down to its fair value, which is measured as the present value of the projected future cash flows of such properties. The factors used to determine fair value include estimates of proved reserves, future commodity prices, timing of future production, future expenditures, and a risk-adjusted discount rate. ​ Our oil & gas mineral interests in unproved properties are also assessed for impairment periodically but at least annually when facts and circumstances indicate that the unproved property will not be transferred to proved properties. Impairment of individual unproved properties whose acquisition costs are relatively significant are assessed on a property-by-property basis, and an impairment loss is recognized if we determine that the unproved property will not be transferred to proved properties. Impairment of unproved properties whose acquisition costs are not individually significant are assessed on a group basis. Any amount of loss to be recognized and the amount of a valuation allowance needed to provide for impairment of those properties is determined by amortizing those properties in the aggregate on the basis of historical experience and other relevant information, such as the relative proportion of such properties on which proved reserves have been found in the past. ​ Upon the sale of a complete depletable group, the book value thereof, less proceeds or salvage value, are charged to income. Upon the sale or retirement of an aggregation of interests which make up less than a complete depletable group, the proceeds are credited to accumulated depreciation, depletion and amortization, unless doing so would significantly alter the depreciation, depletion and amortization rate of the depletable group, in which case a gain or loss would be recorded.
Equity Investments	​ Equity Investments ​ Our investments and ownership interests in equity securities without readily determinable fair values in entities in which we do not have a controlling financial interest or significant influence are accounted for using a measurement alternative other than fair value which is historical cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for identical or similar investments of the same entity. Distributions received on those investments are recorded as income unless those distributions are considered a return on investment, in which case the historical cost is reduced. We account for our ownership interests in Infinitum and Ascend as equity securities without readily determinable fair values. See Note 10 – Equity Investments for further discussion of these investments. ​ Our investments and ownership interests in entities in which we do not have a controlling financial interest are accounted for under the equity method of accounting if we have the ability to exercise significant influence over the entity. Investments accounted for under the equity method are initially recorded at cost, and the difference between the basis of our investment and the underlying equity in the net assets of the joint venture at the investment date, if any, is amortized over the lives of the related assets that gave rise to the difference. ​ In the event our ownership requires a disproportionate sharing of income or loss, we use the hypothetical liquidation at book value (“HLBV”) method to determine the appropriate allocation of income or loss. Under the HLBV method, income or loss of the investee is allocated based on hypothetical amounts that each investor would be entitled to receive if the net assets held were liquidated at book value at the end of each period, adjusted for any contributions made and distributions received during the period. ​ We hold equity method investments in AllDale III, Francis and NGP ET IV. See Note 3 – Variable Interest Entities and Note 10 – Equity Investments for further discussion of our equity method investments. ​ We review our investments for impairment whenever events or changes in circumstances indicate a loss in the value of the investment may be other-than-temporary.
Leases	Leases ​ We lease buildings and equipment under operating lease agreements that provide for the payment of minimum rentals. We also have noncancelable lease agreements with third parties for land and equipment under finance lease obligations. Some of our arrangements within these agreements have both lease and non-lease components, which are generally accounted for separately. We have elected a practical expedient to account for lease and non-lease components as a single lease component for leases of buildings and office equipment. Our leases have approximate lease terms of 1 to 32 years, some of which include automatic renewals up to ten years, which are likely to be exercised and some of which include options to terminate the lease within one year. We also hold numerous mineral reserve leases with both related parties as well as third parties, none of which are accounted for as an operating lease or as a finance lease. ​ We review each agreement to determine if an arrangement within the agreement contains a lease at the inception of an arrangement. Once an arrangement is determined to contain an operating or finance lease with a term greater than 12 months, we recognize a lease liability for the obligation to make lease payments and a right-of-use asset for the right to use the underlying asset for the lease term based on the present value of lease payments over the lease term. The lease term includes all noncancelable periods defined in the lease as well as periods covered by options to extend the lease that we are reasonably certain to exercise. As an implicit borrowing rate cannot be determined under most of our leases, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. ​ Expenses related to leases determined to be operating leases will be recognized on a straight-line basis over the lease term including any reasonably assured renewal periods, while those determined to be finance leases will be recognized following a front-loaded expense profile in which interest and amortization are presented separately in the income statement. The determination of whether a lease is accounted for as a finance lease or an operating lease requires management to make estimates primarily about the fair value of the asset and its estimated economic useful life.
Common Unit-Based Compensation	Common Unit-Based Compensation ​ We maintain the Long-Term Incentive Plan (“LTIP”) for certain key employees and executive officers. Pursuant to the LTIP, unit awards of non-vested “phantom” or notional units, also referred to as “restricted units,” may be granted, which, upon satisfaction of time and performance-based vesting requirements, entitle the LTIP participant to receive ARLP common units. Certain awards may also contain a minimum-value guarantee payable in ARLP common units or cash that would be paid regardless of whether the awards vest, as long as service requirements are met. Annual grant levels, vesting provisions and minimum-value guarantees of restricted units for designated participants are recommended by Mr. Craft, subject to review and approval by the compensation committee of our general partner (“Compensation Committee”). The vesting of all restricted units is subject to the satisfaction of certain financial tests. If it is not probable that the financial tests will be achieved for a particular grant of restricted units, any previously expensed amounts for that grant are reversed, and no future expense will be recognized for that grant other than amounts provided for under minimum-value guarantees. Assuming the financial tests are met, restricted units issued to LTIP participants generally cliff vest on January 1st of the third year following the issuance of such restricted units. We expect to settle restricted unit grants by issuing ARLP common units, except for the portion of the restricted units that will satisfy our tax withholding obligations. We account for forfeitures of non-vested restricted unit grants as they occur. As provided under the distribution equivalent rights (“DERs”) provisions of the LTIP and the terms of the restricted unit awards, all currently outstanding non-vested restricted units include contingent rights to receive quarterly distributions in cash or, at the discretion of the Compensation Committee, phantom units in lieu of cash credited to a bookkeeping account with a value equal to the cash distributions we make to unitholders during the vesting period. If it is not probable the financial tests for a particular grant of restricted units will be met, any previously paid DER amounts for that grant are reversed from Partners’ Capital and recorded as compensation expense and any future DERs, for that grant, if any, will be recognized as compensation expense when paid. ​ The fair value of restricted common unit grants under the LTIP are determined on the grant date of the award and recognized as compensation expense over the requisite service period. The corresponding liability is classified as equity and included in limited partners’ capital in the consolidated financial statements. ​ We utilized the Supplemental Executive Retirement Plan (“SERP”) to provide deferred compensation benefits for certain executive officers. All allocations made to participants under the SERP were made in the form of “phantom” ARLP units. The SERP was administered by the Compensation Committee. ​ Our directors participated in the MGP Amended and Restated Deferred Compensation Plan for Directors (“Directors’ Deferred Compensation Plan”). Pursuant to the Directors’ Deferred Compensation Plan, for amounts deferred either automatically or at the election of the director, a notional account was established and credited with notional common units of ARLP, described in the Directors’ Deferred Compensation Plan as “phantom” units. ​ For both the SERP and Directors’ Deferred Compensation Plan, when quarterly cash distributions were made with respect to ARLP common units, an amount equal to such quarterly distribution was credited to each participant’s notional account as additional phantom units and recorded as compensation expense. All grants of phantom units under the SERP and Directors’ Deferred Compensation Plan vested immediately. ​ On December 16, 2024, the SERP and Directors’ Deferred Compensation Plan were terminated, and final distributions of applicable plan accounts were settled in cash. As of December 31, 2024, we had no further obligations under the SERP or the Directors’ Deferred Compensation Plan.
Workers' Compensation and Pneumoconiosis (Black Lung) Benefits	Workers ’ Compensation and Pneumoconiosis (Black Lung) Benefits ​ We are liable for workers’ compensation benefits for traumatic injuries and benefits for black lung disease (or pneumoconiosis). Both traumatic claims and pneumoconiosis benefits are covered through our self-insured programs. ​ We provide income replacement and medical treatment for work-related traumatic injury claims as required by applicable state laws. Workers’ compensation laws also compensate survivors of workers who suffer employment related deaths. Our liability for traumatic injury claims is the estimated present value of current workers’ compensation benefits, based on our actuarial estimates. Our actuarial calculations are based on a blend of actuarial projection methods and numerous assumptions including claim development patterns, mortality, medical costs and interest rates. ​ Our pneumoconiosis benefits liability is calculated using the service cost method based on the actuarial present value of the estimated pneumoconiosis obligation. Our actuarial calculations are based on numerous assumptions including claim development patterns, medical costs and mortality. Actuarial gains or losses are amortized over the remaining service period of active miners.
Pension Benefits	Pension Benefits ​ The funded status of our pension benefit plan is recognized separately in our consolidated balance sheets as either an asset or liability. The funded status is the difference between the fair value of plan assets and the plan’s benefit obligation. Pension obligations and net periodic benefit costs are actuarially determined and impacted by various assumptions and estimates including expected return on assets, discount rates, mortality assumptions, employee turnover rates and retirement dates. We evaluate our assumptions periodically and make adjustments to these assumptions and the recorded liability as necessary. ​ The discount rate is determined for our pension benefit plan based on an approach specific to our plan. The year end discount rate is determined considering a yield curve comprised of high-quality corporate bonds and the timing of the expected benefit cash flows. ​ The expected long-term rate of return on plan assets is determined based on broad equity and bond indices, the investment goals and objectives, the target investment allocation and on the average annual total return for each asset class. ​ Unrecognized actuarial gains and losses and unrecognized prior service costs and credits are deferred and recorded in accumulated other comprehensive loss until amortized as a component of net periodic benefit cost. Unrecognized actuarial gains and losses in excess of 10% of the greater of the benefit obligation or the market-related value of plan assets are amortized over the participants’ average remaining future years of service.
Asset Retirement Obligations	Asset Retirement Obligations ​ Our coal mining operations are governed by various state statutes and the Federal Surface Mining Control and Reclamation Act of 1977, which establish reclamation and mine closing standards. These regulations require, among other things, restoration of property in accordance with specified standards and an approved reclamation plan. We record a liability for the fair value of an asset retirement obligation in the period incurred or acquired and a corresponding amount is capitalized as part of the related long-lived asset and depreciated on a units-of-production basis. As changes in estimates occur (such as mine plan revisions, changes in estimated costs or changes in anticipated timing of reclamation activities), adjustments to the obligation and asset are recognized at the present value of the change in obligation. For locations that have been fully depleted or closed, the present value of the change in obligation is recorded to operating expense. Accretion of the asset retirement obligation is recognized over time and until reclamation obligations are satisfied. ​ Asset retirement obligations primarily relate to mine site reclamation activities, which includes permanently sealing portals at underground mines, reclaiming the final pits for both our underground mines and past surface mines, removing or covering refuse piles and settling ponds, water treatment, and dismantling preparation plants, other facilities and roadway infrastructure. Federal and state laws require bonds to secure our obligations to reclaim lands used for mining and are typically renewed on an annual basis.
Revenue Recognition	Coal Revenue Recognition ​ Revenues from coal supply contracts with customers, which primarily relate to sales of thermal coal, are recognized at the point in time when control of the coal passes to the customer. We have determined that each ton of coal represents a separate and distinct performance obligation. Our coal supply contracts and other revenue contracts vary in length from short-term to long-term sales contracts and do not typically have significant financing components. Transportation revenues represent the fulfillment costs incurred for the services provided to customers through third-party carriers and for which we are directly reimbursed. Other revenues primarily consist of transloading fees, administrative service revenues from our affiliates, mine safety services and products, other coal contract fees and other handling and service fees. Performance obligations under these contracts are typically satisfied upon transfer of control of the goods or services to our customer which is determined by the contract and could be upon shipment or upon delivery. ​ The estimated transaction price from each of our contracts is based on the total amount of consideration we expect to be entitled to under the contract. Included in the transaction price for certain coal supply contracts is the impact of variable consideration, including quality price adjustments, handling services, government imposition claims, per ton price fluctuations based on certain coal sales price indices and anticipated payments in lieu of shipments. We have constrained the expected value of variable consideration in our estimation of transaction price and only included this consideration to the extent that it is probable that a significant revenue reversal will not occur. The estimated transaction price for each contract is allocated to our performance obligations based on relative standalone selling prices determined at contract inception. Variable consideration is allocated to a specific part of the contract in many instances, such as if the variable consideration is based on production activities for coal delivered during a certain period or the outcome of a customer’s ability to accept coal shipments over a certain period. ​ Contract assets are recorded as trade receivables and reported separately in our consolidated balance sheet from other contract assets as title passes to the customer and our right to consideration becomes unconditional. Payments for coal shipments are typically due within two four weeks ​ Oil & Gas Revenue Recognition ​ Oil & gas royalty revenues are recognized at the point in time when control of the product is transferred to the purchaser by the lessee and collectability of the sales price is reasonably assured. Oil & gas are priced on the delivery date based on prevailing market prices with certain adjustments related to oil quality and physical location. The royalty we receive is tied to a market index, with certain adjustments based on, among other factors, whether a well connects to a gathering or transmission line, quality and heat content of the product, and prevailing supply and demand conditions. ​ We also periodically earn revenue from lease bonuses. We recognize lease bonus revenue when we execute a lease of our mineral interests to exploration and production companies. A lease agreement represents our contract with an operator, which is generally an exploration and production company. The contract will (a) generally transfer the rights to any oil or gas discovered, (b) grant us a right to a specified royalty interest from the operator, and (c) require the operator to commence drilling and complete operations within a specified time period. Control of the minerals transfers to the operator when the lease agreement is executed. At the time we execute the lease agreement, we expect to receive the lease bonus payment within a reasonable time, though in no case more than one year, such that we do not adjust the expected amount of consideration for the effects of any significant financing component. ​ As a non-operator, we have limited visibility into the timing of when new wells start producing. In addition, production statements may not be received for 30 to 90 days or more after the date production is delivered. As a result, we are required to estimate the amount of production delivered to the purchaser and the price that will be received for the sale of the product. The expected sales volumes and prices from our properties are estimated and recorded within the Trade receivables
Income Taxes	Income Taxes ​ We are not a taxable entity for federal or state income tax purposes; the tax effect of our activities accrues to our unitholders. Although publicly traded partnerships as a general rule are taxed as corporations, we qualify for an exemption because at least 90% of our income consists of qualifying income, as defined in Section 7704(c) of the Internal Revenue Code. Net income for financial statement purposes may differ significantly from taxable income reportable to unitholders as a result of differences between the tax basis and financial reporting basis of assets and liabilities and the taxable income allocation requirements under our partnership agreement. Individual unitholders have different investment bases depending upon the timing and price of acquisition of their partnership units. Furthermore, each unitholder’s tax accounting, which is partially dependent upon the unitholder’s tax position, differs from the accounting followed in our consolidated financial statements. Accordingly, the aggregate difference in the basis of our net assets for financial and tax reporting purposes cannot be readily determined because information regarding each unitholder’s tax attributes in our partnership is not available to us. ​ Our subsidiary Alliance Minerals within our Oil & Gas Royalties segment and certain other subsidiaries within our Other, Corporate and Elimination category are subject to federal and state income taxes. We use the liability method of accounting for income taxes, under which deferred tax assets and liabilities are recognized for the future tax consequences of (i) temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities and (ii) operating losses and tax credit carryforwards. Deferred income tax assets and liabilities are based on enacted rates applicable to the future period when those temporary differences are expected to be recovered or settled. The effect of a change in tax status or a change in tax rates on deferred tax assets and liabilities is recognized in the period the change in status is elected or rate change is enacted. A valuation allowance is provided for deferred tax assets when it is more likely than not the deferred tax assets will not be realized.
New Accounting Standards	New Accounting Standards Issued and Adopted ​ In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures ​ In December 2023, the FASB issued ASU 2023-08, Intangibles - Goodwill and Other - Crypto Assets (Subtopic 350-60) ​ New Accounting Standards Issued and Not Yet Adopted ​ Income Taxes (Topic 740): Improvements to Income Tax Disclosures ​ In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2024
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Schedule of advance royalties	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Advance royalties, affiliates (see Note 21– Related-Party Transactions) ​ $ 67,189 ​ $ 64,599 ​ Advance royalties, third-parties ​ 14,497 ​ 14,306 ​ Total advance royalties ​ $ 81,686 ​ $ 78,905 ​

VARIABLE INTEREST ENTITIES (Tab

VARIABLE INTEREST ENTITIES (Tables)	12 Months Ended
	Dec. 31, 2024
VARIABLE INTEREST ENTITIES
Schedule of assets and liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ Assets (liabilities): (in thousands) Cash and cash equivalents ​ $ 5,154 ​ $ 4,690 ​ Trade receivables ​ 11,209 ​ 16,058 ​ Total property, plant and equipment, net ​ 373,093 ​ 389,767 ​ Accounts payable ​ ​ (221) ​ ​ (175) ​ Accrued taxes other than income taxes ​ (870) ​ ​ (958) ​

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	12 Months Ended
	Dec. 31, 2024
Belvedere
ACQUISITIONS
Schedule of assets acquired and liabilities assumed	​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 7,724 ​ Mineral interests in unproved properties ​ ​ 3,667 ​ ​ ​ $ 11,391 ​
Schedule of pro forma income statement	​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2022 ​ (in thousands) ​ ​ ​ ​ Revenue $ 722 ​ Net income 488 ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,420,824 ​ Net income ​ ​ 588,916 ​
Jase
ACQUISITIONS
Schedule of assets acquired and liabilities assumed	​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 35,918 ​ Mineral interests in unproved properties ​ ​ 43,740 ​ Receivables ​ ​ 1,569 ​ Net assets acquired ​ $ 81,227 ​
Schedule of pro forma income statement	​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, ​ ​ 2022 ​ (in thousands) ​ ​ ​ ​ Revenue $ 1,689 ​ Net income 854 ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,430,734 ​ Net income ​ ​ 596,759 ​
Skyland
ACQUISITIONS
Schedule of assets acquired and liabilities assumed	​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ Mineral interests in proved properties ​ $ 8,694 ​ Mineral interests in unproved properties ​ ​ 5,765 ​ Net assets acquired ​ $ 14,459 ​
Schedule of pro forma income statement	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ 2023 2022 ​ ​ ​ (in thousands) ​ ​ ​ (unaudited) ​ Revenues ​ $ 2,568,516 ​ $ 2,423,313 ​ Net income ​ ​ 637,757 ​ ​ 591,140 ​

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2024
FAIR VALUE MEASUREMENTS
Schedule of fair value measurements within the hierarchy	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value ​ ​ Carrying Value Level 1 Level 2 Level 3 ​ ​ (in thousands) ​ December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recorded on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Digital assets (1) ​ $ 45,037 ​ $ 45,037 ​ $ — ​ $ — ​ Contingent consideration ​ $ 13,100 ​ $ — ​ $ — ​ $ 13,100 ​ Additional disclosures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term debt ​ $ 490,387 ​ $ — ​ $ 523,461 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recorded on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent consideration ​ $ 9,900 ​ $ — ​ $ — ​ $ 9,900 ​ Additional disclosures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Long-term debt ​ $ 347,584 ​ $ — ​ $ 347,116 ​ $ — ​ (1) As discussed in Note 2 – Summary of Significant Accounting Policies, we adopted ASU 2023-08 effective January 1, 2024. Prior to our adoption, our digital assets were not recorded at fair value on a recurring basis.
Schedule of fair value measurements inputs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Valuation Technique(s) Unobservable Input Range/Amount (Average) (a) ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent Consideration ​ Option approach methodology simulation ​ Cost of Debt ​ 6.51% - 8.56% ​ ​ ​ ​ ​ Coal price volatility ​ 6.2% ​ ​ ​ ​ ​ Market price of risk adjustment (annual) ​ 6.2% ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contingent Consideration ​ Option approach methodology simulation ​ Cost of Debt ​ 7.27% - 9.08% ​ ​ ​ ​ ​ Coal price volatility ​ 6.3% ​ ​ ​ ​ ​ Market price of risk adjustment (annual) ​ 7.8% ​ ​ ​ ​ ​ ​ ​ ​ ​ (a) Averages represent the arithmetic average of the inputs and is not weighted by a relative fair value or notional amount ​
Schedule of changes in our contingent consideration liability	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 ​ 2023 ​ ​ (in thousands) ​ Beginning balance ​ $ 9,900 ​ $ 10,100 ​ Noncash changes in fair value (1) ​ ​ 10,989 ​ ​ 1,650 ​ Payments ​ ​ (7,789) ​ ​ (1,850) ​ Ending balance ​ $ 13,100 ​ $ 9,900 ​ (1) Noncash changes in the fair value of our continent consideration liability are included in the Operating expenses (excluding depreciation, depletion and amortization) line item within our consolidated statements of income.

INVENTORIES (Tables)

INVENTORIES (Tables)	12 Months Ended
	Dec. 31, 2024
INVENTORIES
Schedule of inventories	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal ​ $ 37,290 ​ $ 56,549 ​ Finished goods (net of reserve for obsolescence of $2,481 and $2,188, respectively) ​ ​ 14,197 ​ ​ 11,752 ​ Work in process ​ ​ 1,560 ​ ​ 2,379 ​ Raw materials ​ ​ 7,192 ​ ​ 6,448 ​ ​ ​ ​ 60,239 ​ ​ 77,128 ​ Supplies (net of reserve for obsolescence of $6,409 and $5,979, respectively) ​ 60,422 ​ 50,428 ​ Total inventories, net ​ $ 120,661 ​ $ 127,556 ​

DIGITAL ASSETS (Tables)

DIGITAL ASSETS (Tables)	12 Months Ended
	Dec. 31, 2024
DIGITAL ASSETS
Schedule of digital assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ ​ ​ Units ​ Cost Basis ​ Fair Value ​ Digital assets: ​ (in thousands, except unit data) ​ Bitcoin ​ ​ 481.89 ​ $ 18,748 ​ $ 45,037 ​ Total ​ ​ ​ ​ $ 18,748 ​ $ 45,037 ​
Schedule of digital assets fair value reconciliation	​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ December 31, ​ ​ ​ 2024 ​ Digital assets: ​ (in thousands) ​ Beginning balance ​ $ 15,811 ​ Additions ​ ​ 10,428 ​ Dispositions ​ ​ (3,597) ​ Fair value gains ​ ​ 22,395 ​ Ending balance ​ $ 45,037 ​

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2024
PROPERTY, PLANT AND EQUIPMENT
Schedule of property, plant and equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Mining equipment and processing facilities ​ $ 2,131,697 ​ $ 1,989,541 ​ Land and coal mineral rights ​ 508,892 ​ 504,736 ​ Oil & gas mineral interests ​ ​ 878,083 ​ ​ 853,350 ​ Buildings, office equipment, improvements and other miscellaneous equipment ​ 315,092 ​ 310,876 ​ Construction, mine development and other projects in progress ​ 213,579 ​ 184,895 ​ Mine development costs ​ 388,192 ​ 329,146 ​ Property, plant and equipment, at cost ​ 4,435,535 ​ 4,172,544 ​ Less accumulated depreciation, depletion and amortization ​ (2,269,265) ​ (2,149,881) ​ Total property, plant and equipment, net ​ $ 2,166,270 ​ $ 2,022,663 ​

EQUITY INVESTMENTS (Tables)

EQUITY INVESTMENTS (Tables)	12 Months Ended
	Dec. 31, 2024
EQUITY INVESTMENTS
Schedule of changes in equity method investments	We account for our ownership interest in the income or loss of AllDale III, Francis and NGP ET IV as equity method investments. We record equity income or loss based on the distribution structure of the investments. The changes in our equity method investments were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ Beginning balance ​ $ 46,503 ​ $ 49,371 ​ $ 26,325 ​ Contributions ​ ​ 2,896 ​ ​ 2,518 ​ ​ 24,087 ​ Equity method investment income (loss) ​ ​ (4,961) ​ ​ (1,468) ​ ​ 5,634 ​ Distributions received ​ ​ (3,788) ​ ​ (3,918) ​ ​ (6,675) ​ Change in our share of net assets ​ ​ (5,118) ​ ​ — ​ ​ — ​ Ending balance ​ $ 35,532 ​ $ 46,503 ​ $ 49,371 ​

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2024
LEASES
Schedule of lease cost and other information	The components of lease expense were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of right-of-use assets ​ $ 95 ​ $ 96 ​ $ 597 ​ Interest on lease liabilities ​ 22 ​ 27 ​ 73 ​ Operating lease cost ​ 3,573 ​ 3,572 ​ 2,884 ​ Short-term lease cost ​ ​ — ​ ​ — ​ ​ — ​ Variable lease cost ​ 1,694 ​ 1,680 ​ 1,665 ​ Total lease cost ​ $ 5,384 ​ $ 5,375 ​ $ 5,219 ​ Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows for operating leases ​ $ 3,668 ​ $ 3,720 ​ $ 2,880 ​ Operating cash flows for finance leases ​ $ 22 ​ $ 27 ​ $ 73 ​ Financing cash flows for finance leases ​ $ 119 ​ $ 363 ​ $ 840 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease obligations: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ $ 1,080 ​ $ 2,596 ​ $ 1,315 ​ ​ Supplemental balance sheet information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Finance leases: ​ ​ ​ ​ ​ ​ ​ Property and equipment finance lease assets, gross ​ $ 1,085 ​ $ 1,085 ​ Accumulated depreciation ​ (602) ​ (507) ​ Property and equipment finance lease assets, net ​ $ 483 ​ $ 578 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ Weighted average remaining lease term ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 14.8 years ​ ​ 11.7 years ​ Finance leases ​ ​ 3.0 years ​ ​ 4.0 years ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 6.1 % ​ ​ 6.0 % ​ Finance leases ​ 4.8 % ​ ​ 4.8 % ​
Schedule of maturities of operating lease liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases Finance leases ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ 2025 ​ $ 2,641 ​ $ 140 ​ 2026 ​ ​ 2,162 ​ ​ 140 ​ 2027 ​ ​ 2,124 ​ ​ 140 ​ 2028 ​ ​ 1,738 ​ ​ — ​ 2029 ​ ​ 1,406 ​ ​ — ​ Thereafter ​ ​ 14,693 ​ ​ — ​ Total lease payments ​ ​ 24,764 ​ ​ 420 ​ Less imputed interest ​ ​ (8,906) ​ ​ (34) ​ Total ​ $ 15,858 ​ $ 386 ​
Schedule of maturities of finance lease liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases Finance leases ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ 2025 ​ $ 2,641 ​ $ 140 ​ 2026 ​ ​ 2,162 ​ ​ 140 ​ 2027 ​ ​ 2,124 ​ ​ 140 ​ 2028 ​ ​ 1,738 ​ ​ — ​ 2029 ​ ​ 1,406 ​ ​ — ​ Thereafter ​ ​ 14,693 ​ ​ — ​ Total lease payments ​ ​ 24,764 ​ ​ 420 ​ Less imputed interest ​ ​ (8,906) ​ ​ (34) ​ Total ​ $ 15,858 ​ $ 386 ​ ​

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	12 Months Ended
	Dec. 31, 2024
LONG-TERM DEBT
Schedule of long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unamortized Discount and ​ ​ ​ Principal ​ Debt Issuance Costs ​ ​ ​ December 31, ​ December 31, ​ ​ 2024 2023 2024 2023 ​ ​ (in thousands) ​ Revolving credit facility ​ $ — ​ $ — ​ $ (7,231) ​ $ (8,118) ​ Term loan ​ 45,703 ​ 60,938 ​ (1,276) ​ (1,416) ​ 8.625% Senior notes due 2029 ​ ​ 400,000 ​ ​ — ​ ​ (8,720) ​ ​ — ​ 7.5% Senior notes due 2025 ​ — ​ 284,607 ​ — ​ (891) ​ Securitization facility ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ June 2020 equipment financing ​ ​ — ​ ​ 2,039 ​ ​ — ​ ​ — ​ February 2024 equipment financing ​ ​ 44,684 ​ ​ — ​ ​ — ​ ​ — ​ ​ ​ 490,387 ​ 347,584 ​ (17,227) ​ (10,425) ​ Less current maturities ​ (26,669) ​ (20,789) ​ 4,394 ​ 451 ​ Total long-term debt ​ $ 463,718 ​ $ 326,795 ​ $ (12,833) ​ $ (9,974) ​
Schedule of aggregate maturities of long-term debt	​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) 2025 ​ $ 26,669 ​ 2026 ​ 28,303 ​ 2027 ​ 29,245 ​ 2028 ​ 6,170 ​ 2029 ​ 400,000 ​ ​ ​ $ 490,387 ​ ​

ACCRUED WORKERS' COMPENSATION_2

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS (Tables)	12 Months Ended
	Dec. 31, 2024
Black lung benefits:
Reconciliation of changes in workers' compensation liability	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 47,975 ​ $ 49,452 ​ Changes in accruals ​ 13,236 ​ 12,155 ​ Payments ​ (14,473) ​ (14,438) ​ Interest accretion ​ 2,037 ​ 2,202 ​ Valuation gain ​ (905) ​ (1,396) ​ Ending balance ​ $ 47,870 ​ $ 47,975 ​
Reconciliation of changes in pneumoconiosis benefit obligation	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligations at beginning of year ​ $ 132,444 ​ $ 104,287 ​ Service cost ​ 3,443 ​ 2,698 ​ Interest cost ​ 6,231 ​ 4,951 ​ Actuarial loss (gain) ​ (13,990) ​ 25,615 ​ Benefits and expenses paid ​ (3,831) ​ (5,107) ​ Benefit obligations at end of year ​ $ 124,297 ​ $ 132,444 ​
Components of pneumoconiosis and workers' compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Service cost $ 3,443 ​ $ 2,698 ​ $ 3,798 ​ Interest cost (1) ​ 6,231 ​ 4,951 ​ 2,991 ​ Net amortization (1) ​ 3,356 ​ 1,382 ​ 1,038 ​ Total pneumoconiosis expense ​ 13,030 ​ 9,031 ​ 7,827 ​ Workers' compensation expense ​ 18,155 ​ 15,152 ​ 11,675 ​ Net periodic benefit cost ​ $ 31,185 ​ $ 24,183 ​ $ 19,502 ​ ________________________________________ (1) Interest cost and net amortization is included in the Other income line item within our consolidated statements of income .
Pneumoconiosis benefits
Black lung benefits:
Reconciliation of changes in the pneumoconiosis benefit obligation recognized in AOCI	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial gain (loss) ​ $ 13,990 ​ $ (25,615) ​ $ 9,840 ​ Reversal of amortization item: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ 3,356 ​ 1,382 ​ 1,038 ​ Total recognized in accumulated other comprehensive loss ​ $ 17,346 ​ $ (24,233) ​ $ 10,878 ​
Schedule of amount recognized in accumulated other comprehensive income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ (in thousands) ​ Amount recognized in accumulated other comprehensive loss consists of: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ $ 32,399 ​ $ 49,745 ​ $ 25,510 ​
Summary of information about amounts recognized in the consolidated balance sheets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Workers’ compensation claims ​ $ 47,870 ​ $ 47,975 ​ Pneumoconiosis benefit claims ​ ​ 124,297 ​ ​ 132,444 ​ Total obligations ​ 172,167 ​ 180,419 ​ Less current portion ​ (14,838) ​ (15,913) ​ Non-current obligations ​ $ 157,329 ​ $ 164,506 ​

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables) - Defined benefit pension plan	12 Months Ended
	Dec. 31, 2024
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Summary of benefit plans for employees	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 ​ ​ (dollars in thousands) ​ Change in benefit obligations: ​ ​ ​ ​ ​ ​ ​ Benefit obligations at beginning of year ​ $ 105,870 ​ $ 104,682 ​ Interest cost ​ 5,107 ​ 5,180 ​ Actuarial loss (gain) ​ (4,509) ​ 2,446 ​ Benefits paid ​ (7,491) ​ (6,438) ​ Benefit obligations at end of year ​ 98,977 ​ 105,870 ​ ​ ​ ​ ​ ​ ​ ​ ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ 97,252 ​ 92,129 ​ Employer contribution ​ 152 ​ — ​ Actual return on plan assets ​ 11,029 ​ 11,561 ​ Benefits paid ​ (7,491) ​ (6,438) ​ Fair value of plan assets at end of year ​ 100,942 ​ 97,252 ​ Funded status at the end of year ​ $ 1,965 ​ $ (8,618) ​ ​ ​ ​ ​ ​ ​ ​ ​ Amounts recognized in balance sheet: ​ ​ ​ ​ ​ ​ ​ Non-current assets ​ $ 1,965 ​ $ — ​ Non-current liabilities ​ $ — ​ $ (8,618) ​ ​ ​ ​ ​ ​ ​ ​ ​ Amounts recognized in accumulated other comprehensive income consists of: ​ ​ ​ ​ ​ ​ ​ Prior service cost ​ $ (10) ​ $ (196) ​ Net actuarial loss ​ ​ (2,694) ​ ​ (11,584) ​ ​ ​ $ (2,704) ​ $ (11,780) ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average assumption to determine benefit obligations as of December 31, ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 5.51% ​ 4.90% ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average assumptions used to determine net periodic benefit cost for the year ended December 31, ​ ​ ​ ​ ​ ​ ​ Discount rate ​ 4.90% ​ 5.10% ​ Expected return on plan assets ​ 7.50% ​ 7.00% ​
Schedule of long-term rate of return assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset allocation ​ As of December 31, 2024 assumption Equity securities ​ 75% ​ Fixed income securities 25% ​ ​ 100% ​
Components of net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ ​ (in thousands) Components of net periodic benefit credit: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest cost ​ $ 5,107 ​ $ 5,180 ​ $ 3,749 ​ Expected return on plan assets ​ (7,031) ​ (6,220) ​ (6,638) ​ Amortization of prior service cost ​ ​ 186 ​ ​ 186 ​ ​ 186 ​ Amortization of net loss ​ 383 ​ 682 ​ 1,963 ​ Net periodic benefit credit (1) ​ $ (1,355) ​ $ (172) ​ $ (740) ​ (1) Nonservice components of net periodic benefit credit are included in the Other income (expense) line item within our consolidated statements of income.
Schedule of other changes in plan assets and benefit obligation recognized in AOCI	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 ​ ​ ​ (in thousands) ​ Other changes in plan assets and benefit obligation recognized in accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ Net actuarial gain ​ $ 8,507 ​ $ 2,894 ​ Reversal of amortization item: ​ ​ ​ ​ ​ ​ ​ Prior service cost ​ ​ 186 ​ ​ 186 ​ Net actuarial loss ​ 383 ​ 682 ​ Total recognized in accumulated other comprehensive loss ​ 9,076 ​ 3,762 ​ Net periodic benefit credit ​ 1,355 ​ 172 ​ Total recognized in net periodic benefit credit and accumulated other comprehensive loss ​ $ 10,431 ​ $ 3,934 ​
Schedule of estimated future benefit payments	​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) ​ ​ ​ ​ ​ 2025 ​ $ 7,832 ​ 2026 ​ 6,700 ​ 2027 ​ 6,830 ​ 2028 ​ 6,924 ​ 2029 ​ 6,996 ​ 2030-2034 ​ 35,431 ​ ​ ​ $ 70,713 ​
Schedule of asset allocation guidelines, actual asset allocations and fair value of Pension Plan assets	​ ​ ​ ​ ​ ​ ​ ​ ​ Percentage of Total Portfolio ​ Minimum Maximum ​ ​ ​ ​ ​ ​ Equity securities ​ 50% ​ 85% ​ Fixed income securities ​ 15% ​ 50% ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 ​ 2023 ​ ​ ​ Level 1 ​ Level 2 ​ Level 3 ​ Total ​ Level 1 ​ Level 2 ​ Level 3 ​ Total ​ ​ ​ (in thousands) Cash and cash equivalents ​ $ 2,243 ​ $ — ​ $ — ​ $ 2,243 ​ $ 1,665 ​ $ — ​ $ — ​ $ 1,665 ​ Equity investments - Individual securities (a): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer discretionary ​ ​ 3,572 ​ ​ — ​ ​ — ​ ​ 3,572 ​ ​ 2,605 ​ ​ — ​ ​ — ​ ​ 2,605 ​ Consumer durables ​ ​ 2,257 ​ ​ — ​ ​ — ​ ​ 2,257 ​ ​ 2,088 ​ ​ — ​ ​ — ​ ​ 2,088 ​ Energy ​ ​ 1,046 ​ ​ — ​ ​ — ​ ​ 1,046 ​ ​ 952 ​ ​ — ​ ​ — ​ ​ 952 ​ Financials ​ ​ 5,302 ​ ​ — ​ ​ — ​ ​ 5,302 ​ ​ 4,852 ​ ​ — ​ ​ — ​ ​ 4,852 ​ Health Care ​ ​ 3,972 ​ ​ — ​ ​ — ​ ​ 3,972 ​ ​ 4,296 ​ ​ — ​ ​ — ​ ​ 4,296 ​ Industrials & materials ​ ​ 4,402 ​ ​ — ​ ​ — ​ ​ 4,402 ​ ​ 4,507 ​ ​ — ​ ​ — ​ ​ 4,507 ​ Information technology & communication ​ ​ 9,052 ​ ​ — ​ ​ — ​ ​ 9,052 ​ ​ 8,102 ​ ​ — ​ ​ — ​ ​ 8,102 ​ Fixed income - Investments (b): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preferred stocks non-convertible ​ ​ 14 ​ ​ — ​ ​ — ​ ​ 14 ​ ​ 37 ​ ​ — ​ ​ — ​ ​ 37 ​ Real return mutual funds ​ ​ 464 ​ ​ — ​ ​ — ​ ​ 464 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ Exchange traded mutual funds ​ ​ 591 ​ ​ — ​ ​ — ​ ​ 591 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ Equity investments - Mutual funds (c): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mid-cap stock funds ​ ​ 11,327 ​ ​ — ​ ​ — ​ ​ 11,327 ​ ​ 11,847 ​ ​ — ​ ​ — ​ ​ 11,847 ​ Small-cap stock funds ​ ​ 3,316 ​ ​ — ​ ​ — ​ ​ 3,316 ​ ​ 4,007 ​ ​ — ​ ​ — ​ ​ 4,007 ​ International stock funds ​ ​ 4,689 ​ ​ — ​ ​ — ​ ​ 4,689 ​ ​ 7,849 ​ ​ — ​ ​ — ​ ​ 7,849 ​ Equity investments - Exchange traded funds (d): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Large-cap blend - S&P 500 index ​ ​ 20,144 ​ ​ — ​ ​ — ​ ​ 20,144 ​ ​ 18,044 ​ ​ — ​ ​ — ​ ​ 18,044 ​ International - Developed markets ​ ​ 3,126 ​ ​ — ​ ​ — ​ ​ 3,126 ​ ​ 3,138 ​ ​ — ​ ​ — ​ ​ 3,138 ​ International - Emerging markets ​ ​ 3,338 ​ ​ — ​ ​ — ​ ​ 3,338 ​ ​ 1,894 ​ ​ — ​ ​ — ​ ​ 1,894 ​ Accrued income (e) ​ ​ — ​ ​ 26 ​ ​ — ​ ​ 26 ​ ​ — ​ ​ 29 ​ ​ — ​ ​ 29 ​ ​ ​ $ 78,855 ​ $ 26 ​ $ — ​ $ 78,881 ​ $ 75,883 ​ $ 29 ​ $ — ​ $ 75,912 ​ Commingled investment funds measured at net asset value (f): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income - Investment grade ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 22,061 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 21,340 ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 100,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 97,252 ​ (a) Equity investments - Individual securities include investments in publicly traded common stock and American Depository Receipts. Publicly traded common stocks are traded on a national securities exchange and investments in common stocks are valued using quoted market prices multiplied by the number of shares owned. American Depository Receipts are negotiable securities issued by a bank representing shares in a foreign company and traded on a national securities exchange. (b) Fixed income - investments include investments in preferred stock, mutual funds and exchange traded funds that are traded on a national securities exchange and valued using quoted market prices multiplied by the number of shares owned. (c) Equity investments - Mutual funds are valued daily in actively traded markets. For purposes of calculating the value, portfolio securities and other assets for which market quotes are readily available are valued at market value. Investments initially valued in currencies other than the U.S. dollars are converted to the U.S. dollar using exchange rates obtained from pricing services. (d) Equity investments – Exchange traded funds are funds that own financial assets and trade on exchanges, generally tracking a specific index. Investments in exchange traded funds are valued using a market approach based on the quoted market prices. (e) Accrued income represents dividends or interest declared, but not received, on equity securities owned at December 31, 2024. (f) Investments measured at fair value using the net asset value per share (or its equivalent) have not been classified within the fair value hierarchy. The fair values of all commingled investment funds are determined based on the net asset values per unit of each of the funds. The net asset values per unit represent the aggregate value of the fund’s assets at fair value less liabilities, divided by the number of units outstanding .

ASSET RETIREMENT OBLIGATIONS (T

ASSET RETIREMENT OBLIGATIONS (Tables)	12 Months Ended
	Dec. 31, 2024
ASSET RETIREMENT OBLIGATIONS
Schedule of activity affecting the asset retirement and mine closing liability	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Beginning balance ​ $ 150,443 ​ $ 149,813 ​ Accretion expense ​ 4,528 ​ 4,433 ​ Payments ​ (1,770) ​ (2,317) ​ Allocation of liability associated with mine development and change in assumptions ​ 5,576 ​ (1,486) ​ Ending balance ​ $ 158,777 ​ $ 150,443 ​
Schedule of estimated payments of asset retirement obligations	​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ December 31, (in thousands) ​ ​ ​ ​ ​ 2025 ​ $ 3,621 ​ 2026 ​ 4,763 ​ 2027 ​ 7,043 ​ 2028 ​ 9,312 ​ 2029 ​ 9,584 ​ Thereafter ​ 244,592 ​ Aggregate undiscounted asset retirement obligations ​ 278,915 ​ Less: effect of discounting ​ (120,138) ​ Total asset retirement obligations ​ 158,777 ​ Less: current portion ​ (3,621) ​ Non-current asset retirement obligations ​ $ 155,156 ​

PARTNERS' CAPITAL (Tables)

PARTNERS' CAPITAL (Tables)	12 Months Ended
	Dec. 31, 2024
PARTNERS' CAPITAL.
Summary of quarterly per unit distribution paid	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 First Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.250 ​ Second Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.350 ​ Third Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.400 ​ Fourth Quarter ​ $ 0.700 ​ $ 0.700 ​ $ 0.500 ​

COMMON UNIT-BASED COMPENSATIO_2

COMMON UNIT-BASED COMPENSATION PLANS (Tables)	12 Months Ended
	Dec. 31, 2024
ARLP LTIP
COMMON UNIT-BASED COMPENSATION PLANS
Summary of non-vested share activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average grant date fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-vested grants at January 1, 2022 ​ 3,130,475 ​ $ 5.59 ​ $ 39,569 ​ Granted (1) ​ 769,907 ​ ​ 14.65 ​ ​ ​ ​ Forfeited ​ (203,249) ​ 6.93 ​ ​ ​ ​ Non-vested grants at December 31, 2022 ​ 3,697,133 ​ ​ 7.40 ​ ​ 75,126 ​ Granted (1) ​ 450,125 ​ ​ 21.54 ​ ​ ​ ​ Vested (2) ​ (1,291,330) ​ 5.02 ​ ​ ​ ​ Forfeited ​ (145,584) ​ 6.86 ​ ​ ​ ​ Non-vested grants at December 31, 2023 ​ 2,710,344 ​ ​ 10.91 ​ ​ 57,405 ​ Granted (1) 455,574 ​ ​ 19.69 ​ ​ ​ ​ Vested (2) (1,582,422) ​ 6.53 ​ ​ ​ ​ Forfeited (124,932) ​ 20.37 ​ ​ ​ ​ Non-vested grants at December 31, 2024 1,458,564 ​ 17.60 ​ ​ 38,346 ​ (1) Restricted units granted have certain minimum-value guarantees per unit, regardless of whether the awards vest . (2) During the years ended December 31, 2024 and 2023, we issued 936,544 and 860,060 unrestricted common units, respectively, to the LTIP participants. The remaining vested units were settled in cash to satisfy tax withholding obligations.
SERP and Deferred Compensation Plans
COMMON UNIT-BASED COMPENSATION PLANS
Summary of activity in share-based plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Phantom units outstanding as of January 1, 2022 ​ 668,698 ​ $ 20.37 ​ $ 8,452 ​ Granted ​ 73,842 ​ ​ 19.44 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2022 ​ 742,540 ​ ​ 20.28 ​ ​ 15,088 ​ Granted ​ 118,737 ​ ​ 20.46 ​ ​ ​ ​ Settled (1) ​ (49,331) ​ ​ 20.27 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2023 ​ 811,946 ​ ​ 20.44 ​ ​ 17,197 ​ Granted ​ 100,757 ​ ​ 22.85 ​ ​ ​ ​ Settled (1) (2) (912,703) ​ ​ 26.37 ​ ​ ​ ​ Phantom units outstanding as of December 31, 2024 — ​ ​ ​ ​ ​ ​ (1) During the years ended December 31, 2024 and 2023, we purchased 54,152 and 27,576 ARLP common units, respectively, on the open market to settle the accounts of participants under the SERP. Units purchased were net of units settled in cash to satisfy tax withholding obligations. (2) On December 16, 2024, the SERP and Directors’ Deferred Compensation Plan were terminated, and final distributions of applicable plan accounts were settled in cash.

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables)	12 Months Ended
	Dec. 31, 2024
REVENUE FROM CONTRACTS WITH CUSTOMERS
Schedule of disaggregation of revenues by type	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ Other, ​ ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ Corporate and ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal Elimination Consolidated ​ ​ ​ (in thousands) ​ Year Ended December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,399,100 ​ $ 712,703 ​ $ — ​ $ — ​ $ — ​ $ 2,111,803 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 138,311 ​ ​ — ​ ​ — ​ ​ 138,311 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 69,676 ​ ​ (69,676) ​ ​ — ​ Transportation revenues ​ ​ 85,142 ​ ​ 27,448 ​ ​ — ​ ​ — ​ ​ — ​ ​ 112,590 ​ Other revenues ​ ​ 11,901 ​ ​ 3,091 ​ ​ 825 ​ ​ 65 ​ ​ 70,122 ​ ​ 86,004 ​ Total revenues ​ $ 1,496,143 ​ $ 743,242 ​ $ 139,136 ​ $ 69,741 ​ $ 446 ​ $ 2,448,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,364,901 ​ $ 845,309 ​ $ — ​ $ — ​ $ — ​ $ 2,210,210 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 137,751 ​ ​ — ​ ​ — ​ ​ 137,751 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 65,572 ​ ​ (65,572) ​ ​ — ​ Transportation revenues ​ ​ 106,150 ​ ​ 36,140 ​ ​ — ​ ​ — ​ ​ — ​ ​ 142,290 ​ Other revenues ​ ​ 10,505 ​ ​ 1,885 ​ ​ 3,774 ​ ​ 42 ​ ​ 60,244 ​ ​ 76,450 ​ Total revenues ​ $ 1,481,556 ​ $ 883,334 ​ $ 141,525 ​ $ 65,614 ​ $ (5,328) ​ $ 2,566,701 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 1,219,943 ​ $ 882,286 ​ $ — ​ $ — ​ $ — ​ $ 2,102,229 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 151,060 ​ ​ — ​ ​ — ​ ​ 151,060 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,624 ​ ​ (60,624) ​ ​ — ​ Transportation revenues ​ ​ 69,541 ​ ​ 44,319 ​ ​ — ​ ​ — ​ ​ — ​ ​ 113,860 ​ Other revenues ​ ​ 6,821 ​ ​ 1,482 ​ ​ 3,837 ​ ​ 56 ​ ​ 40,622 ​ ​ 52,818 ​ Total revenues ​ $ 1,296,305 ​ $ 928,087 ​ $ 154,897 ​ $ 60,680 ​ $ (20,002) ​ $ 2,419,967 ​
Schedule of current coal supply contracts	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2028 and ​ ​ ​ ​ 2025 2026 2027 Thereafter Total ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Illinois Basin Coal Operations coal revenues ​ $ 993,263 ​ $ 634,042 ​ $ 388,356 ​ $ 633,827 ​ $ 2,649,488 ​ Appalachia Coal Operations coal revenues ​ ​ 548,906 ​ ​ 100,010 ​ ​ 30,105 ​ ​ — ​ ​ 679,021 ​ Total coal revenues (1) ​ $ 1,542,169 ​ $ 734,052 ​ $ 418,461 ​ $ 633,827 ​ $ 3,328,509 ​ (1) Coal revenues generally consists of consolidated revenues excluding our Oil & Gas Royalties segment as well as intercompany revenues from our Coal Royalties segment .

CONCENTRATION OF CREDIT RISK _2

CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS (Tables)	12 Months Ended
	Dec. 31, 2024
CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS
Schedule of total revenues from major customers	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ Segment 2024 ​ 2023 ​ 2022 ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Customer A Illinois Basin/Appalachia ​ $ 422,936 ​ $ 332,500 ​ $ — ​ Customer B ​ Illinois Basin ​ ​ 270,448 ​ ​ — ​ ​ 328,406 ​ Customer C ​ Illinois Basin ​ ​ 241,800 ​ ​ 253,573 ​ ​ 260,146 ​ Customer D Illinois Basin/Appalachia ​ — ​ ​ — ​ 228,480 ​

RELATED-PARTY TRANSACTIONS (Tab

RELATED-PARTY TRANSACTIONS (Tables)	12 Months Ended
	Dec. 31, 2024
RELATED-PARTY TRANSACTIONS
Summary of advanced royalties outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WKY CoalPlay ​ ​ ​ ​ ​ ​ ​ Towhead ​ Henderson ​ WKY ​ ​ ​ ​ ​ Craft Foundations ​ Coal ​ Coal ​ CoalPlay ​ ​ ​ ​ ​ ​ ​ Henderson ​ ​ ​ Henderson ​ ​ ​ ​ ​ ​ Tunnel ​ & Union ​ Henderson ​ & Union ​ ​ ​ ​ ​ ​ Ridge ​ Counties, KY ​ County, KY ​ Counties, KY ​ Total ​ ​ ​ Acquired ​ Acquired ​ Acquired ​ Acquired ​ ​ ​ ​ ​ ​ 2005 ​ 2014 ​ 2014 ​ 2015 ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of January 1, 2022 ​ $ 1,500 ​ $ 21,750 ​ $ 17,650 ​ $ 14,713 ​ $ 55,613 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,522 ​ ​ 2,131 ​ ​ 11,250 ​ Recoupment ​ ​ (3,000) ​ ​ (3,255) ​ ​ — ​ ​ — ​ ​ (6,255) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2022 ​ ​ 1,500 ​ ​ 22,092 ​ ​ 20,172 ​ ​ 16,844 ​ ​ 60,608 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,521 ​ ​ 2,131 ​ ​ 11,249 ​ Recoupment ​ ​ (3,000) ​ ​ (4,258) ​ ​ — ​ ​ — ​ ​ (7,258) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2023 ​ ​ 1,500 ​ ​ 21,431 ​ ​ 22,693 ​ ​ 18,975 ​ ​ 64,599 ​ Payments ​ ​ 3,000 ​ ​ 3,597 ​ ​ 2,521 ​ ​ 2,131 ​ ​ 11,249 ​ Recoupment ​ ​ (3,000) ​ ​ (5,380) ​ ​ (258) ​ ​ (21) ​ ​ (8,659) ​ Unrecoupable ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ As of December 31, 2024 ​ $ 1,500 ​ $ 19,648 ​ $ 24,956 ​ $ 21,085 ​ $ 67,189 ​

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2024
INCOME TAXES
Components of income tax expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 16,719 ​ $ 15,917 ​ $ 17,572 ​ State ​ 1,403 ​ 1,336 ​ 1,605 ​ ​ ​ 18,122 ​ 17,253 ​ 19,177 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (2,104) ​ (7,235) ​ 33,038 ​ State ​ (81) ​ (1,738) ​ 1,763 ​ ​ ​ (2,185) ​ (8,973) ​ 34,801 ​ Income tax expense ​ $ 15,937 ​ $ 8,280 ​ $ 53,978 ​
Reconciliation from statutory to effective tax rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Income taxes at statutory rate ​ $ 80,114 ​ $ 135,335 ​ $ 134,849 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: Income taxes at statutory rate on Partnership income not subject to income taxes ​ (61,619) ​ (119,556) ​ (113,925) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Increase (decrease) resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State taxes, net of federal income tax ​ 1,187 ​ 864 ​ 1,492 ​ Change in valuation allowance of deferred tax assets ​ — ​ — ​ (317) ​ Deferred taxes related to tax election ​ ​ — ​ ​ — ​ ​ 37,253 ​ Tax effect of noncontrolling interest income not subject to income taxes ​ ​ (1,058) ​ ​ (1,361) ​ ​ (5,399) ​ Return to accrual adjustments ​ ​ (3,018) ​ ​ (7,008) ​ ​ 69 ​ Other ​ 331 ​ 6 ​ (44) ​ Income tax expense ​ $ 15,937 ​ $ 8,280 ​ $ 53,978 ​
Components of deferred taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 ​ ​ (in thousands) ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Property, plant and equipment ​ $ (33,168) ​ $ (36,453) ​ Digital assets ​ ​ (4,319) ​ ​ — ​ Other ​ ​ (1,268) ​ ​ — ​ Total deferred tax liabilities ​ ​ (38,755) ​ ​ (36,453) ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred tax assets: ​ ​ ​ ​ ​ ​ ​ Federal loss carryovers and credits ​ ​ 9,016 ​ ​ 4,508 ​ State loss carryovers and credits ​ ​ 3,122 ​ ​ 2,126 ​ Capitalized research and development ​ ​ 2,646 ​ ​ 2,567 ​ Other ​ 2 ​ 1,098 ​ Total deferred tax assets ​ ​ 14,786 ​ ​ 10,299 ​ ​ ​ ​ ​ ​ ​ ​ ​ Overall net deferred tax liabilities ​ $ (23,969) ​ $ (26,154) ​

EARNINGS PER LIMITED PARTNER _2

EARNINGS PER LIMITED PARTNER UNIT (Tables)	12 Months Ended
	Dec. 31, 2024
EARNINGS PER LIMITED PARTNER UNIT
Reconciliation of net income (loss) and EPU calculations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands, except per unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP ​ $ 360,855 ​ $ 630,118 ​ $ 586,200 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 and diluted ​ 127,965 ​ 127,180 ​ 127,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per limited partner unit - basic and diluted (1) ​ $ 2.77 ​ $ 4.81 ​ $ 4.39 ​ (1) Diluted EPU gives effect to all potentially dilutive common units outstanding during the period using the treasury stock method. Diluted EPU excludes all potentially dilutive units calculated under the treasury stock method if their effect is anti-dilutive. For the years ended December 31, 2024, 2023 and 2022, the combined total of LTIP, SERP and Directors’ Deferred Compensation Plan units of 1,889 , 2,922 and 3,540 , respectively, were considered anti-dilutive under the treasury stock method.

SUPPLEMENTAL CASH FLOW INFORM_2

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2024
SUPPLEMENTAL CASH FLOW INFORMATION
Schedule of supplemental cash flow information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Cash Paid For: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest ​ $ 44,834 ​ $ 37,126 ​ $ 34,844 ​ Income taxes ​ $ 19,540 ​ $ 13,615 ​ $ 23,794 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-Cash Activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts payable for purchase of property, plant and equipment ​ $ 23,728 ​ $ 14,586 ​ $ 44,281 ​ Right-of-use assets acquired by operating lease ​ $ 1,080 ​ $ 2,596 ​ $ 1,315 ​ Market value of common units distributed under deferred compensation plans before tax withholding requirements ​ $ 34,880 ​ $ 28,906 ​ $ — ​ ​

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2024
SEGMENT INFORMATION
Schedule of reportable segment results	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal Total ​ ​ (in thousands) Year Ended December 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,496,143 ​ $ 743,242 ​ $ 139,136 ​ $ 65 ​ $ 2,378,586 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 69,676 ​ ​ 69,676 ​ Total revenues (1) ​ ​ 1,496,143 ​ ​ 743,242 ​ ​ 139,136 ​ ​ 69,741 ​ ​ 2,448,262 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 937,083 ​ ​ 551,734 ​ ​ 19,853 ​ ​ 25,759 ​ 1,534,429 ​ Transportation expenses ​ ​ 85,142 ​ ​ 27,448 ​ ​ — ​ ​ — ​ ​ 112,590 ​ Other segment items (3) ​ ​ — ​ ​ — ​ ​ 2,325 ​ ​ — ​ ​ 2,325 ​ Segment Adjusted EBITDA (4) ​ 473,918 ​ ​ 164,060 ​ ​ 116,958 ​ ​ 43,982 ​ 798,918 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 1,028,622 ​ ​ 467,463 ​ ​ 818,502 ​ ​ 307,924 ​ 2,622,511 ​ Capital expenditures (6) ​ 301,591 ​ ​ 109,315 ​ ​ — ​ ​ — ​ 410,906 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,481,556 ​ $ 883,334 ​ $ 141,525 ​ $ 42 ​ $ 2,506,457 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 65,572 ​ ​ 65,572 ​ Total revenues (1) ​ ​ 1,481,556 ​ ​ 883,334 ​ ​ 141,525 ​ ​ 65,614 ​ ​ 2,572,029 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 861,288 ​ ​ 516,471 ​ ​ 16,532 ​ ​ 24,451 ​ 1,418,742 ​ Transportation expenses ​ ​ 106,150 ​ ​ 36,140 ​ ​ — ​ ​ — ​ ​ 142,290 ​ Other segment items (3) ​ ​ — ​ ​ — ​ ​ 3,485 ​ ​ — ​ ​ 3,485 ​ Segment Adjusted EBITDA (4) ​ 514,118 ​ ​ 330,723 ​ ​ 121,508 ​ ​ 41,163 ​ 1,007,512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 966,102 ​ ​ 488,427 ​ ​ 781,184 ​ ​ 315,592 ​ 2,551,305 ​ Capital expenditures (6) ​ 257,885 ​ ​ 116,217 ​ ​ — ​ ​ 400 ​ 374,502 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 1,296,305 ​ $ 928,087 ​ $ 154,897 ​ $ 56 ​ $ 2,379,345 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,624 ​ ​ 60,624 ​ Total revenues (1) ​ ​ 1,296,305 ​ ​ 928,087 ​ ​ 154,897 ​ ​ 60,680 ​ ​ 2,439,969 ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (2) ​ 806,080 ​ 464,029 ​ 15,395 ​ 21,871 ​ 1,307,375 ​ Transportation expenses ​ ​ 69,541 ​ ​ 44,319 ​ ​ — ​ ​ — ​ ​ 113,860 ​ Other segment items (3) ​ ​ — ​ ​ (6,663) ​ ​ (3,677) ​ ​ — ​ ​ (10,340) ​ Segment Adjusted EBITDA (4) ​ 420,684 ​ 426,402 ​ 143,179 ​ 38,809 ​ 1,029,074 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total assets (5) ​ 779,018 ​ 431,913 ​ 778,465 ​ 321,587 ​ 2,310,983 ​ Capital expenditures (6) ​ 158,624 ​ 76,603 ​ — ​ 38,276 ​ 273,503 ​ (1) The following is a reconciliation of our total segment revenues to total consolidated revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment revenues ​ $ 2,448,262 ​ $ 2,572,029 ​ $ 2,439,969 ​ Other, Corporate and Elimination revenues - Outside ​ ​ 70,122 ​ ​ 60,244 ​ ​ 40,622 ​ Other, Corporate and Elimination revenues - Intercompany ​ ​ (69,676) ​ ​ (65,572) ​ ​ (60,624) ​ Total consolidated revenues ​ $ 2,448,708 ​ $ 2,566,701 ​ $ 2,419,967 ​ ​ Revenues included in Other, Corporate and Elimination are attributable to intercompany eliminations, which are primarily intercompany coal royalties eliminations, outside revenues at the Matrix Group and other outside miscellaneous sales and revenue activities. ​ (2) Segment Adjusted EBITDA Expense includes operating expenses, coal purchases, if applicable, and other income or expense as adjusted to remove certain items from operating expenses that we characterize as unrepresentative of our ongoing operations such as certain litigation accruals. Segment Adjusted EBITDA Expense is used as a financial measure by our management to assess the operating performance of our segments. Segment Adjusted EBITDA Expense is a key component of Segment Adjusted EBITDA in addition to coal sales, royalty revenues and other revenues. The exclusion of corporate general and administrative expenses from Segment Adjusted EBITDA Expense allows management to focus solely on the evaluation of segment operating performance as it primarily relates to our operating expenses. ​ (3) Other segment items for each reportable segment includes: Appalachia Coal Operations Oil & Gas Royalties ​ (4) Segment Adjusted EBITDA is defined as net income attributable to ARLP before net interest expense, income taxes, depreciation, depletion and amortization and general and administrative expenses modified for certain items that we characterize as unrepresentative of our ongoing operations, such as the change in fair value of digital assets and certain litigation accruals. Segment Adjusted EBITDA is used as a financial measure by Mr. Craft, the Chairman, President and Chief Executive Officer of MGP, who is also our chief operating decision maker (“CODM”), other management and by external users of our financial statements such as investors, commercial banks, research analysts and others. Our CODM uses Segment Adjusted EBITDA in assessing segment performance and deciding how to allocate resources. Segment Adjusted EBITDA provides useful information to our CODM and investors regarding our performance and results of operations because Segment Adjusted EBITDA (i) provides additional information about our core operating performance and ability to generate and distribute cash flow, (ii) provides investors with the financial analytical framework upon which we base financial, operational, compensation and planning decisions, (iii) presents a measurement that investors, rating agencies and debt holders have indicated is useful in assessing us and our results of operations and (iv) allows our CODM and management to focus solely on the evaluation of segment operating profitability as it relates to our revenues and operating expenses, which are primarily controlled by our segments. ​ The following is a reconciliation of total Segment Adjusted EBITDA for our segments to consolidated income before income taxes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Segment Adjusted EBITDA – total segments ​ $ 798,918 ​ $ 1,007,512 ​ $ 1,029,074 ​ Other, Corporate and Elimination profit (loss) ​ (2,464) ​ 4,661 ​ 3,495 ​ General and administrative ​ ​ (82,224) ​ ​ (79,096) ​ ​ (80,425) ​ Depreciation, depletion and amortization ​ ​ (285,446) ​ ​ (267,982) ​ ​ (276,670) ​ Asset Impairments ​ ​ (31,130) ​ ​ — ​ ​ — ​ Interest expense, net ​ ​ (28,007) ​ ​ (26,697) ​ ​ (35,296) ​ Change in fair value of digital assets ​ ​ 22,395 ​ ​ — ​ ​ — ​ Litigation expense accrual ​ (15,250) ​ — ​ — ​ Noncontrolling interest ​ ​ 4,702 ​ ​ 6,052 ​ ​ 1,958 ​ Income before income taxes ​ $ 381,494 ​ $ 644,450 ​ $ 642,136 ​ ​ Other, Corporate and Elimination profit (loss) represents profit (loss) from operating segments below the quantitative thresholds when determining our reportable segments as well as the elimination of intersegment profit (loss) between our reportable segments. The operating segments included are those described as part of our Other, Corporate and Eliminations category. ​ (5) The following is a reconciliation of our total segment assets to total consolidated assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment assets ​ $ 2,622,511 ​ $ 2,551,305 ​ $ 2,310,983 ​ Other, Corporate and Elimination total assets ​ ​ 293,219 ​ ​ 237,121 ​ ​ 417,038 ​ Total consolidated assets ​ $ 2,915,730 ​ $ 2,788,426 ​ $ 2,728,021 ​ ​ (6) Capital expenditures shown exclude $24.7 million, $110.9 million and $92.6 million paid for oil & gas acquisitions in 2024, 2023 and 2022, respectively. See Note 4 – Acquisitions for more information. The following is a reconciliation of our total segment capital expenditures to total consolidated capital expenditures: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment capital expenditures ​ $ 410,906 ​ $ 374,502 ​ $ 273,503 ​ Other, Corporate and Elimination capital expenditures ​ ​ 17,835 ​ ​ 4,836 ​ ​ 12,891 ​ Total consolidated capital expenditures ​ $ 428,741 ​ $ 379,338 ​ $ 286,394 ​ ​
Schedule of reconciliation of our total segment revenues to total consolidated revenues	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment revenues ​ $ 2,448,262 ​ $ 2,572,029 ​ $ 2,439,969 ​ Other, Corporate and Elimination revenues - Outside ​ ​ 70,122 ​ ​ 60,244 ​ ​ 40,622 ​ Other, Corporate and Elimination revenues - Intercompany ​ ​ (69,676) ​ ​ (65,572) ​ ​ (60,624) ​ Total consolidated revenues ​ $ 2,448,708 ​ $ 2,566,701 ​ $ 2,419,967 ​
Schedule of reconciliation of total Segment Adjusted EBITDA for our segments to consolidated income before income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2024 2023 2022 ​ ​ (in thousands) ​ Segment Adjusted EBITDA – total segments ​ $ 798,918 ​ $ 1,007,512 ​ $ 1,029,074 ​ Other, Corporate and Elimination profit (loss) ​ (2,464) ​ 4,661 ​ 3,495 ​ General and administrative ​ ​ (82,224) ​ ​ (79,096) ​ ​ (80,425) ​ Depreciation, depletion and amortization ​ ​ (285,446) ​ ​ (267,982) ​ ​ (276,670) ​ Asset Impairments ​ ​ (31,130) ​ ​ — ​ ​ — ​ Interest expense, net ​ ​ (28,007) ​ ​ (26,697) ​ ​ (35,296) ​ Change in fair value of digital assets ​ ​ 22,395 ​ ​ — ​ ​ — ​ Litigation expense accrual ​ (15,250) ​ — ​ — ​ Noncontrolling interest ​ ​ 4,702 ​ ​ 6,052 ​ ​ 1,958 ​ Income before income taxes ​ $ 381,494 ​ $ 644,450 ​ $ 642,136 ​
Schedule of reconciliation of our total segment assets to total consolidated assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment assets ​ $ 2,622,511 ​ $ 2,551,305 ​ $ 2,310,983 ​ Other, Corporate and Elimination total assets ​ ​ 293,219 ​ ​ 237,121 ​ ​ 417,038 ​ Total consolidated assets ​ $ 2,915,730 ​ $ 2,788,426 ​ $ 2,728,021 ​
Schedule of reconciliation of our total segment capital expenditures to total consolidated capital expenditures	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ ​ 2024 2023 2022 ​ ​ ​ (in thousands) ​ Total segment capital expenditures ​ $ 410,906 ​ $ 374,502 ​ $ 273,503 ​ Other, Corporate and Elimination capital expenditures ​ ​ 17,835 ​ ​ 4,836 ​ ​ 12,891 ​ Total consolidated capital expenditures ​ $ 428,741 ​ $ 379,338 ​ $ 286,394 ​ ​

ORGANIZATION AND PRESENTATION (

ORGANIZATION AND PRESENTATION (Details) $ in Thousands							12 Months Ended
	Dec. 07, 2023 USD ($) a	Sep. 08, 2023 USD ($)	Feb. 22, 2023 USD ($) a	Oct. 26, 2022 USD ($) a	Sep. 09, 2022 USD ($) a	Apr. 05, 2022 USD ($)	Dec. 31, 2024 USD ($) a	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Aug. 22, 2023 USD ($)	Jun. 02, 2022 USD ($)
ORGANIZATION AND PRESENTATION
Royalty acres, net | a							70,000
Oil & gas royalty acquisition							$ 24,733	$ 24,225
Payments for acquisitions of businesses								14,459	$ 92,618
JC Resources acquisition								(72,250)
Revenues							2,448,708	2,566,701	2,419,967
Income from operations							394,129	672,397	667,443
Contributions to equity method investments							(2,896)	(2,518)	(24,087)
Payment to acquire investment								49,560	42,000
Equity investment without readily determinable fair value							$ 92,541	$ 92,541
Infinitum
ORGANIZATION AND PRESENTATION
Payment to acquire investment		$ 24,600							$ 42,000
Ascend
ORGANIZATION AND PRESENTATION
Equity investment without readily determinable fair value										$ 25,000
Francis Renewable Energy
ORGANIZATION AND PRESENTATION
Contributions to equity method investments						$ (20,000)
NGP ET IV
ORGANIZATION AND PRESENTATION
Funding commitment											$ 25,000
Belvedere
ORGANIZATION AND PRESENTATION
Royalty acres, net | a					394
Payments for acquisitions of businesses					$ 11,400
Jase
ORGANIZATION AND PRESENTATION
Royalty acres, net | a				3,928
Payments for acquisitions of businesses				$ 81,200
Skyland
ORGANIZATION AND PRESENTATION
Royalty acres, net | a	2,372
Payments for acquisitions of businesses	$ 14,500
JC Resources
ORGANIZATION AND PRESENTATION
Royalty acres, net | a			2,682
JC Resources acquisition			$ 72,300

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Cash Management (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Cash Management
Book overdrafts	$ 3.3	$ 6.7

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Advance Royalties (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Advance Royalties
Advance royalties, affiliates	$ 67,189	$ 64,599
Advance royalties, third-parties	14,497	14,306
Total advance royalties	$ 81,686	$ 78,905

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Leases (Details)	12 Months Ended
	Dec. 31, 2024
Lease renewal term	10 years
Lease termination option term	1 year
Minimum
Lease term	1 year
Maximum
Lease term	32 years

SUMMARY OF SIGNIFICANT ACCOUN_7

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Revenue Recognition
Fair value digital asset	$ 45,037	$ 15,811
Cumulative Effect, Period of Adoption, Adjustment | ASU 2023-08 - Crypto Assets
Revenue Recognition
Fair value digital asset		$ 6,200
Minimum
Revenue Recognition
Coal shipments, payment period	14 days
Maximum
Revenue Recognition
Coal shipments, payment period	28 days
Pension Plan
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Threshold for amortization of unrecognized actuarial gains and losses (as a percent)	10%

VARIABLE INTEREST ENTITIES - Al

VARIABLE INTEREST ENTITIES - AllDale (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
VARIABLE INTEREST ENTITIES
Carrying value of investment	$ 35,532	$ 46,503	$ 49,371	$ 26,325
AllDale I and II | Cavalier Minerals
VARIABLE INTEREST ENTITIES
Ownership percentage by limited partners	72%
Cavalier Minerals
VARIABLE INTEREST ENTITIES
Ownership interest in VIE (as a percent)	96%
Cavalier Minerals | Bluegrass Minerals
VARIABLE INTEREST ENTITIES
Distributions to be received (as a percent)	25%
Noncontrolling ownership interest (as a percent)	4%
AllDale III
VARIABLE INTEREST ENTITIES
Distribution after hurdles (as a percent)	25%
Specified internal rate of return (as a percent)	0.10%
Percentage of available cash distributed	125%
Carrying value of investment	$ 22,500
VIE, Primary Beneficiary | AllDale I and II | AllDale I and II
VARIABLE INTEREST ENTITIES
Ownership percentage by limited partners	97%
VIE, Primary Beneficiary | AllDale I and II | General Partners' Capital
VARIABLE INTEREST ENTITIES
Distributions to be received (as a percent)	20%
VIE, Primary Beneficiary | AllDale I and II | Limited Partners' Capital
VARIABLE INTEREST ENTITIES
Distributions to be received (as a percent)	80%
VIE, Not Primary Beneficiary | AllDale III | AllDale III
VARIABLE INTEREST ENTITIES
Ownership percentage by limited partners	13.90%

VARIABLE INTEREST ENTITIES - Ba

VARIABLE INTEREST ENTITIES - Bal Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Balance Sheet Related Disclosures
Cash and cash equivalents	$ 136,962	$ 59,813
Trade receivables	166,829	282,622
Total property, plant and equipment, net	2,166,270	2,022,663
Accounts payable	(98,188)	(108,269)
Accrued taxes other than income taxes	(21,051)	(21,007)
AllDale I and II
Balance Sheet Related Disclosures
Cash and cash equivalents	5,154	4,690
Trade receivables	11,209	16,058
Total property, plant and equipment, net	373,093	389,767
Accounts payable	(221)	(175)
Accrued taxes other than income taxes	$ (870)	$ (958)

VARIABLE INTEREST ENTITIES - In

VARIABLE INTEREST ENTITIES - Investments (Detail) - USD ($) $ in Thousands			12 Months Ended
	Jun. 02, 2022	Apr. 05, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
VARIABLE INTEREST ENTITIES
Contributions to equity method investments			$ 2,896	$ 2,518	$ 24,087
Carrying value of investment			35,532	$ 46,503	$ 49,371	$ 26,325
Francis Renewable Energy
VARIABLE INTEREST ENTITIES
Carrying value of investment			4,300
NGP ET IV
VARIABLE INTEREST ENTITIES
Carrying value of investment			$ 8,800
Francis Renewable Energy
VARIABLE INTEREST ENTITIES
Contributions to equity method investments		$ 20,000
Francis Renewable Energy | Francis Renewable Energy
VARIABLE INTEREST ENTITIES
Ownership percentage by limited partners			16.70%
NGP ET IV
VARIABLE INTEREST ENTITIES
Funding commitment	$ 25,000
Contributions to investee to date			$ 9,500
NGP ET IV | NGP ET IV
VARIABLE INTEREST ENTITIES
Ownership percentage by limited partners	3.60%

ACQUISITIONS - Asset acquisitio

ACQUISITIONS - Asset acquisition (Details) $ in Thousands		12 Months Ended
	Feb. 22, 2023 USD ($) a	Dec. 31, 2024 USD ($) a	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
ACQUISITIONS
Royalty acres, net | a		70,000
JC Resources acquisition			$ 64,999
Acquisition Agreement
ACQUISITIONS
Mineral interests in proved properties		$ 5,800	6,500
Mineral interests in unproved properties		10,700	6,700
Miscellaneous Acquisitions
ACQUISITIONS
Mineral interests in proved properties		1,300	6,800	$ 1,300
Mineral interests in unproved properties		$ 6,900	$ 4,300	$ 400
JC Resources
ACQUISITIONS
Royalty acres, net | a	2,682
JC Resources acquisition	$ 65,000
Mineral interests in proved properties	25,400
Mineral interests in unproved properties	$ 37,800

ACQUISITIONS - Business Combina

ACQUISITIONS - Business Combination (Details) $ in Thousands				12 Months Ended
	Dec. 07, 2023 USD ($) a	Oct. 26, 2022 USD ($) a	Sep. 09, 2022 USD ($) a	Dec. 31, 2024 a	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
ACQUISITIONS
Royalty acres, net | a				70,000
Payments for acquisitions of businesses					$ 14,459	$ 92,618
Belvedere
ACQUISITIONS
Royalty acres, net | a			394
Payments for acquisitions of businesses			$ 11,400
Assets acquired and liabilities assumed
Mineral interests in proved properties			7,724
Mineral interests in unproved properties			3,667
Net assets acquired			$ 11,391
Jase
ACQUISITIONS
Royalty acres, net | a		3,928
Payments for acquisitions of businesses		$ 81,200
Assets acquired and liabilities assumed
Mineral interests in proved properties		35,918
Mineral interests in unproved properties		43,740
Receivables		1,569
Net assets acquired		$ 81,227
Skyland
ACQUISITIONS
Royalty acres, net | a	2,372
Payments for acquisitions of businesses	$ 14,500
Assets acquired and liabilities assumed
Mineral interests in proved properties	8,694
Mineral interests in unproved properties	5,765
Net assets acquired	$ 14,459

ACQUISITIONS - Pro Forma (Detai

ACQUISITIONS - Pro Forma (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Belvedere
Acquisitions, additional information
Revenues		$ 722
Net income		488
Pro forma condensed consolidated income statement
Revenues		2,420,824
Net income		588,916
Jase
Acquisitions, additional information
Revenues		1,689
Net income		854
Pro forma condensed consolidated income statement
Revenues		2,430,734
Net income		596,759
Skyland
Pro forma condensed consolidated income statement
Revenues	$ 2,568,516	2,423,313
Net income	$ 637,757	$ 591,140

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2015
FAIR VALUE MEASUREMENTS
Fair value digital asset	$ 45,037	$ 15,811
Aggregate
FAIR VALUE MEASUREMENTS
Payment for contingent consideration	9,600
Hamilton acquisition
FAIR VALUE MEASUREMENTS
Amount of contingent consideration payable			$ 110,000
Estimated fair value | Level 1
FAIR VALUE MEASUREMENTS
Fair value digital asset	45,037
Estimated fair value | Level 2
FAIR VALUE MEASUREMENTS
Long-term debt	523,461	347,116
Estimated fair value | Level 3
FAIR VALUE MEASUREMENTS
Contingent consideration	13,100	9,900
Carrying Value
FAIR VALUE MEASUREMENTS
Fair value digital asset	45,037
Contingent consideration	13,100	9,900
Long-term debt	$ 490,387	$ 347,584

FAIR VALUE MEASUREMENTS - Level

FAIR VALUE MEASUREMENTS - Level 3 (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Changes in contingent consideration liability
Liability, beginning balance	$ 9,900	$ 10,100
Noncash changes in fair value	$ (10,989)	$ (1,650)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization
Payments	$ (7,789)	$ (1,850)
Liability, ending balance	$ 13,100	$ 9,900
Measurement Input, Cost of Debt | Minimum
Fair value measurement input
Contingent consideration, Measurement input	0.0651	0.0727
Measurement Input, Cost of Debt | Maximum
Fair value measurement input
Contingent consideration, Measurement input	0.0856	0.0908
Measurement input, Coal price volatility
Fair value measurement input
Contingent consideration, Measurement input	0.062	0.063
Measurement input, Market price of risk adjustment
Fair value measurement input
Contingent consideration, Measurement input	0.062	0.078

INVENTORIES (Details)

INVENTORIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INVENTORIES
Coal	$ 37,290	$ 56,549
Finished goods (net of reserve for obsolescence)	14,197	11,752
Work in process	1,560	2,379
Raw materials	7,192	6,448
Total operating inventories, net	60,239	77,128
Supplies (net of reserve for obsolescence)	60,422	50,428
Total inventories, net	120,661	127,556
Reduce inventory carrying value to market	24,568	33,296	$ 364
Manufactured goods
INVENTORIES
Reserve for obsolescence	2,481	2,188
Supplies
INVENTORIES
Reserve for obsolescence	$ 6,409	$ 5,979

DIGITAL ASSETS - Balance sheet

DIGITAL ASSETS - Balance sheet (Details) $ in Thousands	Dec. 31, 2024 USD ($) instrument	Dec. 31, 2023 USD ($)
DIGITAL ASSETS
Cost Basis	$ 18,748
Fair Value	$ 45,037	$ 15,811
Bitcoin
DIGITAL ASSETS
Units | instrument	481
Cost Basis	$ 18,748
Fair Value	$ 45,037

DIGITAL ASSETS - Reconciliation

DIGITAL ASSETS - Reconciliation (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Digital assets:
Beginning balance	$ 15,811
Additions	10,428
Dispositions	(3,597)
Fair value gains	22,395
Ending balance	45,037
Gains on disposal of digital assets	$ 2,100

DIGITAL ASSETS - Adoption (Deta

DIGITAL ASSETS - Adoption (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
DIGITAL ASSETS
Fair value digital asset	$ 45,037	$ 15,811
ASU 2023-08 - Crypto Assets | Cumulative Effect, Period of Adoption, Adjustment
DIGITAL ASSETS
Fair value digital asset		$ 6,200

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	$ 4,435,535	$ 4,172,544
Less accumulated depreciation, depletion and amortization	(2,269,265)	(2,149,881)
Total property, plant and equipment, net	2,166,270	2,022,663
Depreciation	$ 287,100	276,400	$ 273,800
Minimum
PROPERTY, PLANT AND EQUIPMENT
Estimated useful life	1 year
Maximum
PROPERTY, PLANT AND EQUIPMENT
Estimated useful life	33 years
Mining equipment and processing facilities
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	$ 2,131,697	1,989,541
Land and coal mineral rights
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	508,892	504,736
Coal reserves not subject to depletion	14,100	13,400
Oil & gas mineral interests
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	878,083	853,350
Unproved properties	377,500	411,600
Buildings, office equipment, improvements and other miscellaneous equipment
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	315,092	310,876
Construction, mine development and other projects in progress
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	213,579	184,895
Mine development costs
PROPERTY, PLANT AND EQUIPMENT
Property, plant and equipment, at cost	388,192	329,146
Mine development costs	$ 67,200	$ 44,400

LONG-LIVED ASSET IMPAIRMENTS (D

LONG-LIVED ASSET IMPAIRMENTS (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 15, 2024	Dec. 31, 2024	Nov. 14, 2024	Dec. 31, 2023	Dec. 31, 2022
Asset impairment charges
Carrying value		$ 2,915,730		$ 2,788,426	$ 2,728,021
Asset impairments		$ 31,130
MC Mining
Asset impairment charges
Carrying value	$ 70,200		$ 101,300
Asset impairments	$ 31,100

EQUITY INVESTMENTS - Equity met

EQUITY INVESTMENTS - Equity method (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 05, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Equity Investments
Beginning balance		$ 46,503	$ 49,371	$ 26,325
Contributions		2,896	2,518	24,087
Equity method investment income (loss)		(4,961)	(1,468)	5,634
Distributions received		(3,788)	(3,918)	(6,675)
Change in our share of net assets		(5,118)
Other income (expense)		(2,062)	218	4,355
Ending balance		35,532	$ 46,503	$ 49,371
AllDale III
Equity Investments
Ending balance		$ 22,500
Francis Renewable Energy
Equity Investments
Contributions	$ 20,000

EQUITY INVESTMENTS - Non-equity

EQUITY INVESTMENTS - Non-equity method (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 08, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2024	Aug. 22, 2023
Equity securities without readily determinable fair value
Equity securities		$ 92,541		$ 92,541
Contributions		49,560	$ 42,000
Ending balance		$ 92,541
Infinitum
Equity securities without readily determinable fair value
Contributions	$ 24,600		$ 42,000
Ascend
Equity securities without readily determinable fair value
Equity securities					$ 25,000

LEASES - Lease expense (Details

LEASES - Lease expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES
Amortization of right-of-use assets	$ 95	$ 96	$ 597
Interest on lease liabilities	22	27	73
Operating lease cost	3,573	3,572	2,884
Variable lease cost	1,694	1,680	1,665
Total lease cost	5,384	5,375	5,219
Rental expense	$ 7,400	$ 5,700	$ 5,100

LEASES - Cash flow (Details)

LEASES - Cash flow (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES
Operating cash flows for operating leases	$ 3,668	$ 3,720	$ 2,880
Operating cash flows for finance leases	22	27	73
Financing cash flows for finance leases	119	363	840
Operating leases, Right-of-use assets obtained in exchange for lease obligations	$ 1,080	$ 2,596	$ 1,315

LEASES - Balance Sheet (Details

LEASES - Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Lease balance sheet information
Property and equipment finance lease assets, gross	$ 1,085	$ 1,085
Accumulated depreciation	(602)	(507)
Property and equipment finance lease assets, net	$ 483	$ 578
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization	Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization

LEASES - Weighted Average (Deta

LEASES - Weighted Average (Details)	Dec. 31, 2024	Dec. 31, 2023
LEASES
Weighted average remaining lease term of operating leases	14 years 9 months 18 days	11 years 8 months 12 days
Weighted average remaining lease term of finance leases	3 years	4 years
Weighted average discount rate of operating leases (as a percent)	6.10%	6%
Weighted average discount rate of finance leases (as a percent)	4.80%	4.80%

LEASES - Maturities (Details)

LEASES - Maturities (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Operating leases
2025	$ 2,641
2026	2,162
2027	2,124
2028	1,738
2029	1,406
Thereafter	14,693
Total lease payments	24,764
Less imputed interest	(8,906)
Total	$ 15,858
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Operating Lease, Liability, Noncurrent, Other Liabilities, Current
Finance leases
2025	$ 140
2026	140
2027	140
Total lease payments	420
Less imputed interest	(34)
Total	$ 386
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current, Other Liabilities, Noncurrent

LONG-TERM DEBT - Components (De

LONG-TERM DEBT - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Jun. 12, 2024	Dec. 31, 2023	Apr. 24, 2017
Principal
Aggregate maturities of long-term debt	$ 490,387		$ 347,584
Less current maturities	(26,669)		(20,789)
Total long-term debt	463,718		326,795
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(17,227)		(10,425)
Less current maturities	4,394		451
Total unamortized debt issuance costs	(12,833)		(9,974)
Revolving credit facility
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(7,231)		(8,118)
Term loan
Principal
Aggregate maturities of long-term debt	45,703		60,938
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(1,276)		(1,416)
8.625% Senior Notes due 2029
Principal
Aggregate maturities of long-term debt	400,000
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	$ (8,720)
Interest rate (as a percent)	8.625%	8.625%
7.5% Senior notes due 2025
Principal
Aggregate maturities of long-term debt			284,607
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current			(891)
Interest rate (as a percent)	7.50%			7.50%
June 2020 equipment financing
Principal
Aggregate maturities of long-term debt			$ 2,039
February 2024 equipment financing
Principal
Aggregate maturities of long-term debt	$ 44,684

LONG-TERM DEBT - Credit Facilit

LONG-TERM DEBT - Credit Facility (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 13, 2023	Dec. 31, 2024	Dec. 31, 2023
Long-Term Debt
Debt issuance costs incurred		$ 11,442	$ 12,376
Credit Agreement
Long-Term Debt
Maximum borrowing capacity	$ 425,000
Increase of maximum borrowing capacity	100,000
Minimum liquidity to extend maturity	$ 200,000
Periodic payments (as a percent)	6.25%
Debt issuance costs incurred		$ 1,800	$ 12,400
Minimum debt to cash flow ratio for restriction to apply on cash distribution	1
Interest coverage ratio	3
Actual cash flow to interest expense ratio for trailing twelve months		37.97
Credit Agreement | Overnight Bank Funding Rate
Long-Term Debt
Basis spread for variable interest rate (as a percent)	0.50%
Credit Agreement | Daily Simple Secured Overnight Financing Rate
Long-Term Debt
Basis spread for variable interest rate (as a percent)	1%
Credit Agreement | Alliance Coal
Long-Term Debt
ARLP debt arrangements requirements, debt to cash flow ratio	1.5
Actual debt to cash flow ratio for trailing twelve months		0.17
Credit Agreement | Alliance Coal and Intermediate Partnership
Long-Term Debt
ARLP debt arrangements requirements, debt to cash flow ratio	2.5
Actual debt to cash flow ratio for trailing twelve months		0.91
Swingline subfacility
Long-Term Debt
Maximum borrowing capacity	$ 15,000
Term loan
Long-Term Debt
Maximum borrowing term loan	$ 75,000
Effective interest rate (as a percent)		7.71%
Other letters of credit
Long-Term Debt
Maximum borrowing capacity		$ 5,000
Letters of credit outstanding		5,000
Revolving credit facility
Long-Term Debt
Letters of credit outstanding		41,000
Debt available for borrowing		$ 384,000
Annual commitment fee percentage, undrawn portion		0.50%
Restricted net assets of subsidiaries		$ 649,200

LONG-TERM DEBT - Senior Notes (

LONG-TERM DEBT - Senior Notes (Details) - USD ($) $ in Thousands			12 Months Ended
	Jun. 12, 2024	Apr. 24, 2017	Dec. 31, 2024	Dec. 31, 2023
Issuance of Senior Notes
Debt issuance costs incurred			$ 11,442	$ 12,376
8.625% Senior Notes due 2029
Issuance of Senior Notes
Principal amount	$ 400,000
Term	5 years
Interest rate (as a percent)	8.625%		8.625%
Debt issuance costs incurred	$ 9,700
8.625% Senior Notes due 2029 | Scenario One
Issuance of Senior Notes
Maximum redeemable debt (as a percent)	35%
Redemption price to principal (as a percent)	108.625%
8.625% Senior Notes due 2029 | Scenario Two
Issuance of Senior Notes
Maximum redeemable debt (as a percent)	40%
Redemption price to principal (as a percent)	108.625%
7.5% Senior notes due 2025
Issuance of Senior Notes
Principal amount		$ 400,000
Term		8 years
Interest rate (as a percent)		7.50%	7.50%

LONG-TERM DEBT - Securitization

LONG-TERM DEBT - Securitization Facility (Details) - Securitization facility - USD ($) $ in Millions	Jan. 31, 2025	Dec. 31, 2024
Long-Term Debt
Maximum borrowing capacity	$ 75	$ 90
Letters of credit outstanding		14.8
Debt available for borrowing		73
Facility outstanding amount		$ 0

LONG-TERM DEBT - Equipment fina

LONG-TERM DEBT - Equipment financing and other (Details) - USD ($) $ in Millions	Feb. 28, 2024	Jun. 05, 2020
June 2020 equipment financing
Long-Term Debt
Principal amount		$ 14.7
Term		48 months
Effective interest rate (as a percent)		6.10%
February 2024 equipment financing
Long-Term Debt
Principal amount	$ 54.6
Term	48 months
Effective interest rate (as a percent)	8.29%

LONG-TERM DEBT - Maturities (De

LONG-TERM DEBT - Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Aggregate maturities of long-term debt
2025	$ 26,669
2026	28,303
2027	29,245
2028	6,170
2029	400,000
Aggregate maturities of long-term debt	$ 490,387	$ 347,584

ACCRUED WORKERS' COMPENSATION_3

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS - WorkComp Roll (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Reconciliation of changes in the workers' compensation liability
Beginning balance	$ 47,975	$ 49,452
Changes in accruals	13,236	12,155
Payments	(14,473)	(14,438)
Interest accretion	2,037	2,202
Valuation loss	(905)	(1,396)
Ending balance	$ 47,870	$ 47,975
Estimated present value of future obligations and other information
Workers' compensation discount rate	5.17%	4.66%
Letters of credit outstanding to secure workers compensation obligations	$ 106,800	$ 99,400
Receivables for traumatic injury claims	$ 3,700	$ 4,100

ACCRUED WORKERS' COMPENSATION_4

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS - Pneum Roll (Details) - Pneumoconiosis benefits - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of the changes in black lung benefit obligations
Benefit obligations at beginning of year	$ 132,444	$ 104,287
Service cost	3,443	2,698	$ 3,798
Interest cost	6,231	4,951	2,991
Actuarial loss (gain)	(13,990)	25,615
Benefits and expenses paid	(3,831)	(5,107)
Benefit obligations at end of year	$ 124,297	$ 132,444	$ 104,287

ACCRUED WORKERS' COMPENSATION_5

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS - AOCL (Details) - Pneumoconiosis benefits - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other changes in plan assets and benefit obligations recognized in accumulated other comprehensive loss:
Net actuarial gain (loss)	$ 13,990	$ (25,615)	$ 9,840
Reversal of amortization item: Net actuarial loss (gain)	3,356	1,382	1,038
Total recognized in accumulated other comprehensive Income	$ 17,346	$ (24,233)	$ 10,878
Estimated present value of future obligations and other information
Pneumoconiosis discount rate	5.51%	4.81%	5%
Amount recognized in accumulated other comprehensive income consists of:
Net actuarial loss	$ 32,399	$ 49,745	$ 25,510

ACCRUED WORKERS' COMPENSATION_6

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS - Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS
Workers' compensation claims	$ 47,870	$ 47,975	$ 49,452
Pneumoconiosis benefit claims	124,297	132,444
Total obligations	172,167	180,419
Less current portion	(14,838)	(15,913)
Non-current obligations	$ 157,329	$ 164,506

ACCRUED WORKERS' COMPENSATION_7

ACCRUED WORKERS' COMPENSATION AND PNEUMOCONIOSIS - Benefit cost (Details) - Pneumoconiosis benefits - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Black lung benefits:
Service cost	$ 3,443	$ 2,698	$ 3,798
Interest cost	$ 6,231	$ 4,951	$ 2,991
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Net amortization	$ 3,356	$ 1,382	$ 1,038
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Total pneumoconiosis and workers' compensation expense	$ 13,030	$ 9,031	$ 7,827
Workers' compensation expense	18,155	15,152	11,675
Net periodic benefit cost	$ 31,185	$ 24,183	$ 19,502

EMPLOYEE BENEFIT PLANS - Define

EMPLOYEE BENEFIT PLANS - Defined Contribution (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
PSSP
Defined Contribution Plans
Contribution expense	$ 25.5	$ 21.8	$ 19.4

EMPLOYEE BENEFIT PLANS - Obliga

EMPLOYEE BENEFIT PLANS - Obligations, Assets, Reported Amounts (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Change in benefit obligations:
Benefit obligations at beginning of year	$ 105,870	$ 104,682
Interest cost	5,107	5,180	$ 3,749
Actuarial gain	(4,509)	2,446
Benefits paid	(7,491)	(6,438)
Benefit obligations at end of year	98,977	105,870	104,682
Change in plan assets:
Fair value of plan assets at beginning of year	97,252	92,129
Employer contribution	152
Actual return on plan assets	11,029	11,561
Benefits paid	(7,491)	(6,438)
Fair value of plan assets at end of year	100,942	97,252	$ 92,129
Funded status at the end of year	1,965	(8,618)
Amounts recognized in balance sheet:
Non-current assets	1,965
Non-current liability		(8,618)
Amount recognized in accumulated other comprehensive income consists of:
Prior service cost	(10)	(196)
Net actuarial loss	(2,694)	(11,584)
Amounts recognized in accumulated other comprehensive income	$ (2,704)	$ (11,780)
Weighted-average assumption to determine benefit obligations
Discount rate	5.51%	4.90%
Weighted-average assumptions used to determine net periodic benefit cost
Discount rate	4.90%	5.10%
Expected return on plan assets	7.50%	7%

EMPLOYEE BENEFIT PLANS - Assump

EMPLOYEE BENEFIT PLANS - Assumptions (Details) - Pension Plan	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Asset allocation assumptions
Asset allocation assumption	100%
Actual return on plan assets (as a percent)	11.30%	12.50%
Equity securities
Asset allocation assumptions
Asset allocation assumption	75%
Fixed income securities
Asset allocation assumptions
Asset allocation assumption	25%

EMPLOYEE BENEFIT PLANS - Expens

EMPLOYEE BENEFIT PLANS - Expense (Credit) (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net periodic benefit cost:
Interest cost	$ 5,107	$ 5,180	$ 3,749
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]		Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Expected return on plan assets	(7,031)	$ (6,220)	$ (6,638)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Amortization of prior service cost	186	$ 186	$ 186
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration]		Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Amortization of net loss	383	$ 682	$ 1,963
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Net periodic benefit cost	(1,355)	$ (172)	$ (740)
Other changes in plan assets and benefit obligations recognized in accumulated other comprehensive loss:
Net actuarial gain	8,507	2,894	10,148
Reversal of amortization item: Prior service cost	186	186	186
Reversal of amortization item: Net actuarial loss	383	682	1,963
Total recognized in accumulated other comprehensive Income	9,076	3,762	12,297
Net periodic benefit cost	(1,355)	(172)	$ (740)
Total recognized in net periodic benefit credit and accumulated other comprehensive loss	$ (10,431)	$ (3,934)

EMPLOYEE BENEFIT PLANS - Estima

EMPLOYEE BENEFIT PLANS - Estimated Benefit Payments (Details) - Pension Plan $ in Thousands	Dec. 31, 2024 USD ($)
Estimated future benefit payments
2025	$ 7,832
2026	6,700
2027	6,830
2028	6,924
2029	6,996
2030-2034	35,431
Estimated future benefit payments	70,713
Expected contribution for pension plan in next year	$ 0

EMPLOYEE BENEFIT PLANS - Asset

EMPLOYEE BENEFIT PLANS - Asset Allocations (Details) - Pension Plan	Dec. 31, 2024
Equity securities | Minimum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Target allocation	50%
Equity securities | Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Target allocation	85%
Fixed income securities | Minimum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Target allocation	15%
Fixed income securities | Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Target allocation	50%

EMPLOYEE BENEFIT PLANS - Plan A

EMPLOYEE BENEFIT PLANS - Plan Assets (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	$ 100,942	$ 97,252	$ 92,129
Total other than commingled investment funds measured at net asset value
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	78,881	75,912
Total other than commingled investment funds measured at net asset value | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	78,855	75,883
Total other than commingled investment funds measured at net asset value | Level 2
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	26	29
Cash And Cash Equivalents
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	2,243	1,665
Cash And Cash Equivalents | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	2,243	1,665
Consumer discretionary
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,572	2,605
Consumer discretionary | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,572	2,605
Consumer durables
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	2,257	2,088
Consumer durables | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	2,257	2,088
Energy
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	1,046	952
Energy | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	1,046	952
Financials
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	5,302	4,852
Financials | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	5,302	4,852
Health Care
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,972	4,296
Health Care | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,972	4,296
Industrials & materials
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	4,402	4,507
Industrials & materials | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	4,402	4,507
Information technology & communication
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	9,052	8,102
Information technology & communication | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	9,052	8,102
Preferred stocks non-convertible
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	14	37
Preferred stocks non-convertible | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	14	37
Real return mutual funds
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	464
Real return mutual funds | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	464
Exchange traded mutual funds
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	591
Exchange traded mutual funds | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	591
Mid-cap stock funds
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	11,327	11,847
Mid-cap stock funds | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	11,327	11,847
Small-cap stock funds
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,316	4,007
Small-cap stock funds | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,316	4,007
International stock funds
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	4,689	7,849
International stock funds | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	4,689	7,849
Large-cap blend - S&P 500 index
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	20,144	18,044
Large-cap blend - S&P 500 index | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	20,144	18,044
International - Developed markets
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,126	3,138
International - Developed markets | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,126	3,138
Accrued income
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	26	29
Accrued income | Level 2
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	26	29
International - Emerging markets
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,338	1,894
International - Emerging markets | Level 1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	3,338	1,894
Fixed income - Investment grade
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Defined benefit plan, fair value of plan assets	$ 22,061	$ 21,340

ASSET RETIREMENT OBLIGATIONS -

ASSET RETIREMENT OBLIGATIONS - Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Asset retirement and mine closing liability
Balance at the beginning of the period	$ 150,443	$ 149,813
Accretion expense	4,528	4,433
Payments	(1,770)	(2,317)
Allocation of liability associated with mine development and change in assumptions	5,576	(1,486)
Balance at the end of the period	$ 158,777	$ 150,443

ASSET RETIREMENT OBLIGATIONS _2

ASSET RETIREMENT OBLIGATIONS - Estimated Payments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Estimated payments of asset retirement obligations:
2025	$ 3,621
2026	4,763
2027	7,043
2028	9,312
2029	9,584
Thereafter	244,592
Aggregate undiscounted asset retirement obligations	278,915
Less: effect of discounting	(120,138)	$ (116,200)
Total asset retirement obligations	158,777	150,443	$ 149,813
Less: current portion	(3,621)
Non-current asset retirement obligations	155,156	146,925
Surety bonds outstanding to performance of reclamation obligations	$ 170,100	$ 173,500

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions	1 Months Ended
	Apr. 30, 2024	Dec. 31, 2024
Contractual Commitments
Settlement awarded to other party	$ 15.3
Settlement accrual		$ 15.3
Commitments related to planned capital projects
Contractual Commitments
Contractual Obligation		$ 140.7

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Other (Details) - Property and casualty insurance $ in Millions	Oct. 01, 2024 USD ($)
Commitments And Contingencies
Aggregate maximum insurance limit	$ 100
Insurance deductible	$ 1.5
Waiting period one	75 days
Waiting period two	90 days
Overall aggregate deductible	$ 25
Participating interest retained (in percent)	2.50%

PARTNERS' CAPITAL - Distributio

PARTNERS' CAPITAL - Distributions (Details) - USD ($) $ / shares in Units, $ in Millions

3 Months Ended

12 Months Ended

Jan. 28, 2025

Dec. 31, 2024

Sep. 30, 2024

Jun. 30, 2024

Mar. 31, 2024

Dec. 31, 2023

Sep. 30, 2023

Jun. 30, 2023

Mar. 31, 2023

Dec. 31, 2022

Sep. 30, 2022

Jun. 30, 2022

Mar. 31, 2022

Dec. 31, 2024

PARTNERS' CAPITAL.

Quarterly distribution paid (in dollars per unit)

$ 0.7

$ 0.7

$ 0.7

$ 0.7

$ 0.7

$ 0.7

$ 0.7

$ 0.7

$ 0.5

$ 0.4

$ 0.35

$ 0.25

Period following quarter end for distribution of available cash

45 days

Declaration date for Limited Partner distribution

Jan. 28, 2025

Distribution date for Limited Partner distribution

Feb. 14, 2025

Record date for Limited Partner distribution

Feb. 07, 2025

Distribution declared (in dollars per unit)

$ 0.7

Quarterly distribution declared

$ 89.6

PARTNERS' CAPITAL - Repurchase

PARTNERS' CAPITAL - Repurchase (Details) - Limited Partners' Capital - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Partners' capital
Increase in authorization amount	$ 93.5
Remaining authorized amount		$ 80.6		$ 6.5
Repurchase and retire authorization	$ 100
Number of units retired		0	929,842	0
Repurchase price (in dollars per unit)			$ 20.9
Treasury units retired			$ 19.4
Aggregate
Partners' capital
Number of units retired		6,390,446
Repurchase price (in dollars per unit)		$ 17.67
Treasury units retired		$ 112.9

COMMON UNIT-BASED COMPENSATIO_3

COMMON UNIT-BASED COMPENSATION PLANS - LTIP Grants (Details) - ARLP LTIP - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 28, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Number of units
Balance at the beginning of the period (in units)		2,710,344	3,697,133	3,130,475
Granted (in units)	341,137	455,574	450,125	769,907
Vested (in units)		(1,582,422)	(1,291,330)
Forfeited (in units)		(124,932)	(145,584)	(203,249)
Balance at the end of the period (in units)		1,458,564	2,710,344	3,697,133
Weighted average grant date fair value per unit
Balance at the beginning of the period (in dollars per unit)		$ 10.91	$ 7.4	$ 5.59
Granted (in dollars per unit)		19.69	21.54	14.65
Vested (in dollars per unit)		6.53	5.02
Forfeited (in dollars per unit)		20.37	6.86	6.93
Balance at the end of the period (in dollars per unit)		$ 17.6	$ 10.91	$ 7.4
Intrinsic value (in dollars)
Intrinsic value of outstanding grants (in dollars)		$ 38,346	$ 57,405	$ 75,126	$ 39,569
Other information
Common units issued		936,544	860,060

COMMON UNIT-BASED COMPENSATIO_4

COMMON UNIT-BASED COMPENSATION PLANS - LTIP Other (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 28, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other information
Cash settlement of grants		$ 21,786
ARLP LTIP
Other information
Unit-based compensation expense		8,300	$ 10,400	$ 9,400
Total unit-based obligation recorded		16,900	$ 19,500
Unrecognized compensation expense (in dollars)		$ 8,800
Weighted-average period for recognition of expense		1 year 6 months
Additional grants authorized (in units)	354,261
Units granted	341,137	455,574	450,125	769,907

COMMON UNIT-BASED COMPENSATIO_5

COMMON UNIT-BASED COMPENSATION PLANS - SERP and Directors (Details) - SERP and Deferred Compensation Plans - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Number of units
Balance at the beginning of the period (in units)	811,946	742,540	668,698
Granted (in units)	100,757	118,737	73,842
Settled (in units)	(912,703)	(49,331)
Balance at the end of the period (in units)		811,946	742,540
Weighted average grant date fair value per unit
Balance at the beginning of the period (in dollars per unit)	$ 20.44	$ 20.28	$ 20.37
Granted (in dollars per unit)	22.85	20.46	19.44
Settled (in dollars per unit)	$ (26.37)	20.27
Balance at the end of the period (in dollars per unit)		$ 20.44	$ 20.28
Intrinsic value (in dollars)
Intrinsic value of outstanding grants (in dollars)		$ 17,197	$ 15,088	$ 8,452
Other information
Purchased for awards (in shares)	54,152	27,576
Unit-based compensation expense	$ 2,300	$ 2,400	$ 1,400
Total unit-based obligation recorded		$ 16,600

REVENUE FROM CONTRACTS WITH C_3

REVENUE FROM CONTRACTS WITH CUSTOMERS - Disaggregation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of revenues
Revenues	$ 2,448,708	$ 2,566,701	$ 2,419,967
Coal sales
Disaggregation of revenues
Revenues	2,111,803	2,210,210	2,102,229
Oil & gas royalties
Disaggregation of revenues
Revenues	138,311	137,751	151,060
Transportation
Disaggregation of revenues
Revenues	112,590	142,290	113,860
Other revenues
Disaggregation of revenues
Revenues	86,004	76,450	52,818
Coal Royalties
Disaggregation of revenues
Revenues	69,741	65,614	60,680
Operating Segments
Disaggregation of revenues
Revenues	2,448,262	2,572,029	2,439,969
Operating Segments | Illinois Basin Coal
Disaggregation of revenues
Revenues	1,496,143	1,481,556	1,296,305
Operating Segments | Illinois Basin Coal | Coal sales
Disaggregation of revenues
Revenues	1,399,100	1,364,901	1,219,943
Operating Segments | Illinois Basin Coal | Transportation
Disaggregation of revenues
Revenues	85,142	106,150	69,541
Operating Segments | Illinois Basin Coal | Other revenues
Disaggregation of revenues
Revenues	11,901	10,505	6,821
Operating Segments | Appalachia Coal
Disaggregation of revenues
Revenues	743,242	883,334	928,087
Operating Segments | Appalachia Coal | Coal sales
Disaggregation of revenues
Revenues	712,703	845,309	882,286
Operating Segments | Appalachia Coal | Transportation
Disaggregation of revenues
Revenues	27,448	36,140	44,319
Operating Segments | Appalachia Coal | Other revenues
Disaggregation of revenues
Revenues	3,091	1,885	1,482
Operating Segments | Oil & Gas Royalties
Disaggregation of revenues
Revenues	139,136	141,525	154,897
Operating Segments | Oil & Gas Royalties | Oil & gas royalties
Disaggregation of revenues
Revenues	138,311	137,751	151,060
Operating Segments | Oil & Gas Royalties | Other revenues
Disaggregation of revenues
Revenues	825	3,774	3,837
Operating Segments | Coal Royalties
Disaggregation of revenues
Revenues	69,741	65,614	60,680
Operating Segments | Coal Royalties | Coal royalties
Disaggregation of revenues
Revenues	69,676	65,572	60,624
Operating Segments | Coal Royalties | Other revenues
Disaggregation of revenues
Revenues	65	42	56
Other, Corporate and Elimination
Disaggregation of revenues
Revenues	446	(5,328)	(20,002)
Other, Corporate and Elimination | Coal royalties
Disaggregation of revenues
Revenues	(69,676)	(65,572)	(60,624)
Other, Corporate and Elimination | Other revenues
Disaggregation of revenues
Revenues	70,122	60,244	40,622
Elimination | Coal Royalties
Disaggregation of revenues
Revenues	$ (69,676)	$ (65,572)	$ (60,624)

REVENUE FROM CONTRACTS WITH C_4

REVENUE FROM CONTRACTS WITH CUSTOMERS - Supply contracts (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Performance obligations unsatisfied or partially unsatisfied
Total	$ 3,328,509
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 1,542,169
Expected timing of satisfaction period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 734,052
Expected timing of satisfaction period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 418,461
Expected timing of satisfaction period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 633,827
Expected timing of satisfaction period	1 year
Illinois Basin Coal
Performance obligations unsatisfied or partially unsatisfied
Total	$ 2,649,488
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 993,263
Expected timing of satisfaction period	1 year
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 634,042
Expected timing of satisfaction period	1 year
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 388,356
Expected timing of satisfaction period	1 year
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 633,827
Expected timing of satisfaction period	1 year
Appalachia Coal
Performance obligations unsatisfied or partially unsatisfied
Total	$ 679,021
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 548,906
Expected timing of satisfaction period	1 year
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 100,010
Expected timing of satisfaction period	1 year
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 30,105
Expected timing of satisfaction period	1 year
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Performance obligations unsatisfied or partially unsatisfied
Expected timing of satisfaction period	1 year

CONCENTRATION OF CREDIT RISK _3

CONCENTRATION OF CREDIT RISK AND MAJOR CUSTOMERS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Major Customers
Revenues	$ 2,448,708	$ 2,566,701	$ 2,419,967
Trade receivables	$ 166,829	$ 282,622
Revenue | Geographic Concentration Risk | Europe, Africa, Asia, North America and South America
Major Customers
Concentration of risk (as a percent)	17.30%	15.70%	12.50%
Revenue | Customer Concentration Risk | Customer A
Major Customers
Revenues	$ 422,936	$ 332,500
Revenue | Customer Concentration Risk | Customer B
Major Customers
Revenues	270,448		$ 328,406
Revenue | Customer Concentration Risk | Customer C
Major Customers
Revenues	241,800	253,573	260,146
Revenue | Customer Concentration Risk | Customer D
Major Customers
Revenues			$ 228,480
Trade accounts receivable | Customer Concentration Risk | Major Customers
Major Customers
Trade receivables	$ 50,100	$ 54,300

RELATED-PARTY TRANSACTIONS - Af

RELATED-PARTY TRANSACTIONS - Affiliate Royalty Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction
As of the beginning of period	$ 64,599
As of the end of period	67,189	$ 64,599
Coal lease
Related Party Transaction
As of the beginning of period	64,599	60,608	$ 55,613
Payments	11,249	11,249	11,250
Recoupment	(8,659)	(7,258)	(6,255)
As of the end of period	67,189	64,599	60,608
Tunnel Ridge
Related Party Transaction
As of the beginning of period	1,500	1,500	1,500
Payments	3,000	3,000	3,000
Recoupment	(3,000)	(3,000)	(3,000)
As of the end of period	1,500	1,500	1,500
WKY CoalPlay | December 2014 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
As of the beginning of period	21,431	22,092	21,750
Payments	3,597	3,597	3,597
Recoupment	(5,380)	(4,258)	(3,255)
As of the end of period	19,648	21,431	22,092
WKY CoalPlay | December 2014 coal lease - Henderson County, Kentucky
Related Party Transaction
As of the beginning of period	22,693	20,172	17,650
Payments	2,521	2,521	2,522
Recoupment	(258)
As of the end of period	24,956	22,693	20,172
WKY CoalPlay | February 2015 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
As of the beginning of period	18,975	16,844	14,713
Payments	2,131	2,131	2,131
Recoupment	(21)
As of the end of period	$ 21,085	$ 18,975	$ 16,844

RELATED-PARTY TRANSACTIONS - Cr

RELATED-PARTY TRANSACTIONS - Craft Foundations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2018
Tunnel Ridge
Related Party Transaction
Related party purchase	$ 0.2
Tunnel Ridge
Related Party Transaction
Annual minimum coal royalties	3
Payments for earned royalties	$ 9.4	$ 12.1	$ 12.3
Tunnel Ridge | Joseph W Craft III Foundation | Tunnel Ridge
Related Party Transaction
Property ownership (as a percent)				50%
Tunnel Ridge | Kathleen S Craft Foundation | Tunnel Ridge
Related Party Transaction
Property ownership (as a percent)				50%

RELATED-PARTY TRANSACTIONS - WK

RELATED-PARTY TRANSACTIONS - WKY CoalPlay (Details) - WKY CoalPlay - USD ($) $ in Millions	1 Months Ended
	Feb. 28, 2015	Dec. 31, 2014
February 2015 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
Initial term of lease	20 years
Percentage of earned royalty on coal sale price	4%
Annual minimum coal royalties	$ 2.1
December 2014 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
Initial term of lease		20 years
Percentage of earned royalty on coal sale price		4%
Annual minimum coal royalties		$ 3.6
December 2014 coal lease - Henderson County, Kentucky
Related Party Transaction
Annual minimum coal royalties		$ 2.5

INCOME TAXES - Components (Deta

INCOME TAXES - Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
Federal	$ 16,719	$ 15,917	$ 17,572
State	1,403	1,336	1,605
Total current income tax expense	18,122	17,253	19,177
Deferred:
Federal	(2,104)	(7,235)	33,038
State	(81)	(1,738)	1,763
Total deferred income tax expense	(2,185)	(8,973)	34,801
Income tax expense	$ 15,937	$ 8,280	$ 53,978

INCOME TAXES - Tax election (De

INCOME TAXES - Tax election (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Taxes
Deferred tax liability		$ 23,969	$ 26,154
AllDale I and II
Taxes
Acquisition gain	$ 177,000
Change in accounting
Taxes
Deferred tax liability				$ 37,300

INCOME TAXES - Reconciliation (

INCOME TAXES - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
Income taxes at statutory rate	$ 80,114	$ 135,335	$ 134,849
Less: Income taxes at statutory rate on Partnership income not subject to income taxes	(61,619)	(119,556)	(113,925)
Increase (decrease) resulting from:
State taxes, net of federal income tax	1,187	864	1,492
Change in valuation allowance of deferred tax assets			(317)
Deferred taxes related to tax election			37,253
Tax effect of noncontrolling interest income not subject to income taxes	(1,058)	(1,361)	(5,399)
Return to accrual adjustments	(3,018)	(7,008)	69
Other	331	6	(44)
Income tax expense	$ 15,937	$ 8,280	$ 53,978

INCOME TAXES - Deferred (Detail

INCOME TAXES - Deferred (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax liabilities:
Property, plant and equipment	$ (33,168)	$ (36,453)
Digital assets	(4,319)
Other	(1,268)
Total deferred tax liabilities	(38,755)	(36,453)
Deferred tax assets:
Federal loss carryovers and credits	9,016	4,508
State loss carryovers and credits	3,122	2,126
Capitalized research and development	2,646	2,567
Other	2	1,098
Total deferred tax assets	14,786	10,299
Overall net deferred tax liabilities	$ (23,969)	$ (26,154)

EARNINGS PER LIMITED PARTNER _3

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

SUPPLEMENTAL CASH FLOW INFORM_3

SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash Paid For:
Interest	$ 44,834	$ 37,126	$ 34,844
Income taxes	19,540	13,615	23,794
Non-Cash Activity:
Accounts payable for purchase of property, plant and equipment	23,728	14,586	44,281
Right-of-use assets acquired by operating lease	1,080	2,596	$ 1,315
Market value of common units distributed under deferred compensation plans before tax withholding requirements	$ 34,880	$ 28,906

SEGMENT INFORMATION - General (

SEGMENT INFORMATION - General (Details)	12 Months Ended
	Dec. 31, 2024 segment
Segment Information
Number of reportable segments	4
Number of coal reportable segments	2
Number of mining complex	7
Coal Royalties
Segment Information
Coal sold by coal operations (in percent)	63%

SEGMENT INFORMATION - Results (

SEGMENT INFORMATION - Results (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reportable segment results
Revenues	$ 2,448,708	$ 2,566,701	$ 2,419,967
Segment Adjusted EBITDA Expense	1,534,429	1,418,742	1,307,375
Other segment items	2,325	3,485	(10,340)
Segment Adjusted EBITDA	798,918	1,007,512	1,029,074
Total assets	2,915,730	2,788,426	2,728,021
Capital expenditures	428,741	379,338	286,394
Transportation
Reportable segment results
Revenues	112,590	142,290	113,860
Transportation expenses	112,590	142,290	113,860
Other revenues
Reportable segment results
Revenues	86,004	76,450	52,818
Coal Royalties
Reportable segment results
Revenues	69,741	65,614	60,680
Operating Segments, Excluding Corporate and Elimination
Reportable segment results
Revenues	2,378,586	2,506,457	2,379,345
Operating Segments, Excluding Corporate and Elimination | Illinois Basin Coal
Reportable segment results
Revenues	1,496,143	1,481,556	1,296,305
Operating Segments, Excluding Corporate and Elimination | Appalachia Coal
Reportable segment results
Revenues	743,242	883,334	928,087
Operating Segments, Excluding Corporate and Elimination | Oil & Gas Royalties
Reportable segment results
Revenues	139,136	141,525	154,897
Operating Segments, Excluding Corporate and Elimination | Coal Royalties
Reportable segment results
Revenues	65	42	56
Operating Segments
Reportable segment results
Revenues	2,448,262	2,572,029	2,439,969
Segment Adjusted EBITDA Expense	798,918	1,007,512	1,029,074
Total assets	2,622,511	2,551,305	2,310,983
Capital expenditures	410,906	374,502	273,503
Operating Segments | Illinois Basin Coal
Reportable segment results
Revenues	1,496,143	1,481,556	1,296,305
Segment Adjusted EBITDA Expense	937,083	861,288	806,080
Segment Adjusted EBITDA	473,918	514,118	420,684
Total assets	1,028,622	966,102	779,018
Capital expenditures	301,591	257,885	158,624
Operating Segments | Illinois Basin Coal | Transportation
Reportable segment results
Revenues	85,142	106,150	69,541
Transportation expenses	85,142	106,150	69,541
Operating Segments | Illinois Basin Coal | Other revenues
Reportable segment results
Revenues	11,901	10,505	6,821
Operating Segments | Appalachia Coal
Reportable segment results
Revenues	743,242	883,334	928,087
Segment Adjusted EBITDA Expense	551,734	516,471	464,029
Other segment items			(6,663)
Segment Adjusted EBITDA	164,060	330,723	426,402
Total assets	467,463	488,427	431,913
Capital expenditures	109,315	116,217	76,603
Operating Segments | Appalachia Coal | Transportation
Reportable segment results
Revenues	27,448	36,140	44,319
Transportation expenses	27,448	36,140	44,319
Operating Segments | Appalachia Coal | Other revenues
Reportable segment results
Revenues	3,091	1,885	1,482
Operating Segments | Oil & Gas Royalties
Reportable segment results
Revenues	139,136	141,525	154,897
Segment Adjusted EBITDA Expense	19,853	16,532	15,395
Other segment items	2,325	3,485	(3,677)
Segment Adjusted EBITDA	116,958	121,508	143,179
Total assets	818,502	781,184	778,465
Operating Segments | Oil & Gas Royalties | Other revenues
Reportable segment results
Revenues	825	3,774	3,837
Operating Segments | Coal Royalties
Reportable segment results
Revenues	69,741	65,614	60,680
Segment Adjusted EBITDA Expense	25,759	24,451	21,871
Segment Adjusted EBITDA	43,982	41,163	38,809
Total assets	307,924	315,592	321,587
Capital expenditures		400	38,276
Operating Segments | Coal Royalties | Coal royalties
Reportable segment results
Revenues	69,676	65,572	60,624
Operating Segments | Coal Royalties | Other revenues
Reportable segment results
Revenues	65	42	56
Elimination | Coal Royalties
Reportable segment results
Revenues	(69,676)	(65,572)	(60,624)
Other, Corporate and Elimination
Reportable segment results
Revenues	446	(5,328)	(20,002)
Total assets	293,219	237,121	417,038
Capital expenditures	17,835	4,836	12,891
Other, Corporate and Elimination | Coal royalties
Reportable segment results
Revenues	(69,676)	(65,572)	(60,624)
Other, Corporate and Elimination | Other revenues
Reportable segment results
Revenues	$ 70,122	$ 60,244	$ 40,622

SEGMENT INFORMATION - EBITDA Re

SEGMENT INFORMATION - EBITDA Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEGMENT INFORMATION
Segment Adjusted Ebitda	$ 798,918	$ 1,007,512	$ 1,029,074
General and administrative	(82,224)	(79,096)	(80,425)
Depreciation, depletion and amortization	(285,446)	(267,982)	(276,670)
Asset impairments	(31,130)
Interest expense, net	(28,007)	(26,697)	(35,296)
Change in fair value of digital assets	22,395
Litigation expense accrual	(15,250)
Noncontrolling interest	4,702	6,052	1,958
INCOME BEFORE INCOME TAXES	381,494	644,450	642,136
Other, Corporate and Elimination
SEGMENT INFORMATION
Other, Corporate and Elimination profit (loss)	$ (2,464)	$ 4,661	$ 3,495

SEGMENT INFORMATION - Assets (D

SEGMENT INFORMATION - Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEGMENT INFORMATION
Total assets	$ 2,915,730	$ 2,788,426	$ 2,728,021
Oil and gas acquisitions	24,700	110,900	92,600
Capital expenditures	428,741	379,338	286,394
Operating Segments
SEGMENT INFORMATION
Total assets	2,622,511	2,551,305	2,310,983
Capital expenditures	410,906	374,502	273,503
Other, Corporate and Elimination
SEGMENT INFORMATION
Total assets	293,219	237,121	417,038
Capital expenditures	$ 17,835	$ 4,836	$ 12,891

SUBSEQUENT EVENT (Details)

SUBSEQUENT EVENT (Details) $ in Millions	Feb. 28, 2025 USD ($)
Subsequent event
Subsequent Event
Funding commitment	$ 25

SCHEDULE I - CONDENSED FINANCIA

SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - BALANCE SHEETS (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CURRENT ASSETS:
Cash and cash equivalents	$ 136,962	$ 59,813
Total current assets	513,230	516,121
OTHER ASSETS:
Total other assets	236,230	249,642
TOTAL ASSETS	2,915,730	2,788,426	$ 2,728,021
CURRENT LIABILITIES:
Accrued taxes other than income taxes	21,051	21,007
Total current liabilities	233,142	227,467
Total liabilities	1,062,197	929,829
PARTNERS' CAPITAL:
Limited Partners - Common Unitholders 128,061,981 and 127,125,437 units outstanding, respectively	1,867,850	1,896,027
TOTAL LIABILITIES AND PARTNERS' CAPITAL	2,915,730	2,788,426
Parent company
CURRENT ASSETS:
Cash and cash equivalents	1,942	2,043
Total current assets	1,942	2,043
OTHER ASSETS:
Investments in consolidated subsidiaries	1,866,102	1,894,158
Total other assets	1,866,102	1,894,158
TOTAL ASSETS	1,868,044	1,896,201
CURRENT LIABILITIES:
Accrued taxes other than income taxes	194	174
Total current liabilities	194	174
Total liabilities	194	174
PARTNERS' CAPITAL:
Limited Partners - Common Unitholders 128,061,981 and 127,125,437 units outstanding, respectively	1,867,850	1,896,027
TOTAL LIABILITIES AND PARTNERS' CAPITAL	$ 1,868,044	$ 1,896,201

SCHEDULE I - CONDENSED FINANC_2

SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - BALANCE SHEETS (Parenthetical) (Details) - shares	Dec. 31, 2024	Dec. 31, 2023
Condensed Financial Statements
Common units outstanding	128,061,981	127,125,437
Parent company
Condensed Financial Statements
Common units outstanding	128,061,981	127,125,437

SCHEDULE I - CONDENSED FINANC_3

SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - OPERATIONS (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
EXPENSES:
General and administrative	$ 82,224	$ 79,096	$ 80,425
Total operating expenses	2,054,579	1,894,304	1,752,524
LOSS FROM OPERATIONS	394,129	672,397	667,443
Interest income	7,222	9,394	2,035
NET INCOME ATTRIBUTABLE TO ARLP	360,855	630,118	586,200
NET INCOME ATTRIBUTABLE TO ARLP
GENERAL PARTNER		1,384	9,010
LIMITED PARTNERS	$ 360,855	$ 628,734	$ 577,190
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
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - BASIC (in units)	127,964,744	127,180,312	127,195,219
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - DILUTED (in units)	127,965,000	127,180,000	127,195,000
Parent company
EXPENSES:
General and administrative	$ 301	$ 151
Total operating expenses	301	151
LOSS FROM OPERATIONS	(301)	(151)
Interest income	94	57
Equity in earnings of consolidated subsidiaries	361,062	630,212	$ 586,200
NET INCOME ATTRIBUTABLE TO ARLP	360,855	630,118	586,200
NET INCOME ATTRIBUTABLE TO ARLP
GENERAL PARTNER		1,384	9,010
LIMITED PARTNERS	$ 360,855	$ 628,734	$ 577,190
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
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - BASIC (in units)	127,964,744	127,180,312	127,195,219
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - DILUTED (in units)	127,964,744	127,180,312	127,195,219

SCHEDULE I - CONDENSED FINANC_4

SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - CASH FLOWS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
CASH FLOWS FROM OPERATING ACTIVITIES	$ 803,131	$ 824,231	$ 802,349
CASH FLOWS FROM FINANCING ACTIVITIES:
Distributions paid to Partners	(363,430)	(364,579)	(196,347)
Net cash used in financing activities	(285,318)	(507,119)	(225,391)
NET CHANGE IN CASH AND CASH EQUIVALENTS	77,149	(236,210)	173,620
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	59,813	296,023	122,403
CASH AND CASH EQUIVALENTS AT END OF PERIOD	136,962	59,813	296,023
Parent company
CASH FLOWS FROM OPERATING ACTIVITIES:
CASH FLOWS FROM OPERATING ACTIVITIES	363,329	364,448	196,348
CASH FLOWS FROM FINANCING ACTIVITIES:
Distributions paid to Partners	(363,430)	(364,579)	(196,347)
Net cash used in financing activities	(363,430)	(364,579)	(196,347)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(101)	(131)	1
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	2,043	2,174	2,173
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 1,942	$ 2,043	$ 2,174

SCHEDULE I - CONDENSED FINANC_5

SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT - Narrative (Details) - Parent company - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Condensed Financial Statements
Maximum undiscounted future payment obligation	$ 21.9
Cash contribution by affiliated entity	$ 363.4	$ 364.6	$ 196.3