Alliance Resource Partners (ARLP) 10-Q 8 Aug 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 08, 2023
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2023
Entity 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
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
Entity Shell Company	false
Title of 12(b) Security	Common units
Trading Symbol	ARLP
Security Exchange Name	NASDAQ
Entity Common Units Outstanding		127,125,437
Entity Central Index Key	0001086600
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
CURRENT ASSETS:
Cash and cash equivalents	$ 284,899	$ 296,023
Trade receivables	213,754	241,412
Other receivables	11,672	8,601
Inventories, net	128,940	77,326
Advance royalties	5,824	7,556
Prepaid expenses and other assets	18,842	26,675
Total current assets	663,931	657,593
PROPERTY, PLANT AND EQUIPMENT:
Property, plant and equipment, at cost	4,040,872	3,931,422
Less accumulated depreciation, depletion and amortization	(2,112,693)	(2,050,754)
Total property, plant and equipment, net	1,928,179	1,880,668
OTHER ASSETS:
Advance royalties	74,476	67,713
Equity method investments	46,789	49,371
Equity securities	42,000	42,000
Operating lease right-of-use assets	17,621	14,950
Other long-term assets	14,947	15,726
Total other assets	195,833	189,760
TOTAL ASSETS	2,787,943	2,728,021
CURRENT LIABILITIES:
Accounts payable	109,093	95,122
Accrued taxes other than income taxes	22,852	22,967
Accrued payroll and related expenses	35,220	39,623
Accrued interest	4,312	5,000
Workers' compensation and pneumoconiosis benefits	14,135	14,099
Other current liabilities	24,377	53,790
Current maturities, long-term debt, net	37,771	24,970
Total current liabilities	247,760	255,571
LONG-TERM LIABILITIES:
Long-term debt, excluding current maturities, net	379,427	397,203
Pneumoconiosis benefits	101,578	100,089
Accrued pension benefit	12,028	12,553
Workers' compensation	41,170	39,551
Asset retirement obligations	143,550	142,254
Long-term operating lease obligations	14,645	12,132
Deferred income tax liabilities	35,416	35,814
Other liabilities	25,612	24,828
Total long-term liabilities	753,426	764,424
Total liabilities	1,001,186	1,019,995
COMMITMENTS AND CONTINGENCIES - (NOTE 3)
ARLP Partners' Capital:
Limited Partners - Common Unitholders 127,125,437 and 127,195,219 units outstanding, respectively	1,801,682	1,656,025
General Partner's interest		66,548
Accumulated other comprehensive loss	(39,926)	(41,054)
Total ARLP Partners' Capital	1,761,756	1,681,519
Noncontrolling interest	25,001	26,507
Total Partners' Capital	1,786,757	1,708,026
TOTAL LIABILITIES AND PARTNERS' CAPITAL	$ 2,787,943	$ 2,728,021

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Jun. 30, 2023	Dec. 31, 2022
CONDENSED CONSOLIDATED BALANCE SHEETS
Common units outstanding	127,125,437	127,195,219

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
SALES AND OPERATING REVENUES:
Revenues	$ 641,836	$ 619,878	$ 1,304,758	$ 1,083,300
EXPENSES:
Outside coal purchases	4,209	151	4,209	151
General and administrative	20,130	22,480	41,215	41,102
Depreciation, depletion and amortization	68,639	67,690	134,189	131,830
Total operating expenses	457,907	442,556	913,503	816,713
INCOME FROM OPERATIONS	183,929	177,322	391,255	266,587
Interest expense (net of interest capitalized for the three and six months ended June 30, 2023 and 2022 of $0, $171, $1,407 and $241, respectively)	(9,433)	(9,397)	(22,109)	(19,059)
Interest income	2,625	93	5,415	128
Equity method investment income (loss)	(1,994)	1,585	(1,942)	2,468
Other income (expense)	177	579	(396)	1,146
INCOME BEFORE INCOME TAXES	175,304	170,182	372,223	251,270
INCOME TAX EXPENSE	3,999	6,331	8,240	49,046
NET INCOME	171,305	163,851	363,983	202,224
LESS: NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTEREST	(1,515)	(323)	(3,008)	(613)
NET INCOME ATTRIBUTABLE TO ARLP	169,790	163,528	360,975	201,611
NET INCOME ATTRIBUTABLE TO ARLP
GENERAL PARTNER		2,050	1,384	3,481
LIMITED PARTNERS	$ 169,790	$ 161,478	$ 359,591	$ 198,130
EARNINGS PER LIMITED PARTNER UNIT - BASIC (in dollars per unit)	$ 1.30	$ 1.23	$ 2.75	$ 1.51
EARNINGS PER LIMITED PARTNER UNIT - DILUTED (in dollars per unit)	$ 1.30	$ 1.23	$ 2.75	$ 1.51
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - BASIC (in units)	127,183,439	127,195,219	127,236,097	127,195,219
WEIGHTED-AVERAGE NUMBER OF UNITS OUTSTANDING - DILUTED (in units)	127,183,000	127,195,000	127,236,000	127,195,000
Product
EXPENSES:
Operating expenses (excluding depreciation, depletion and amortization)	$ 334,402	$ 316,850	$ 673,125	$ 578,873
Coal sales
SALES AND OPERATING REVENUES:
Revenues	560,331	531,807	1,139,115	920,167
Oil & gas royalties
SALES AND OPERATING REVENUES:
Revenues	33,087	39,287	67,584	72,683
Transportation
SALES AND OPERATING REVENUES:
Revenues	30,527	35,385	60,765	64,757
EXPENSES:
Operating expenses (excluding depreciation, depletion and amortization)	30,527	35,385	60,765	64,757
Other revenues
SALES AND OPERATING REVENUES:
Revenues	$ 17,891	$ 13,399	$ 37,294	$ 25,693

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
CONDENSED CONSOLIDATED STATEMENTS OF INCOME
Interest expense, interest capitalized	$ 1,216	$ 171	$ 2,623	$ 241

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
NET INCOME	$ 171,305	$ 163,851	$ 363,983	$ 202,224
OTHER COMPREHENSIVE INCOME:
OTHER COMPREHENSIVE INCOME	563	794	1,128	1,584
COMPREHENSIVE INCOME	171,868	164,645	365,111	203,808
Less: Comprehensive income attributable to noncontrolling interest	(1,515)	(323)	(3,008)	(613)
COMPREHENSIVE INCOME ATTRIBUTABLE TO ARLP	170,353	164,322	362,103	203,195
Defined benefit pension plan
OTHER COMPREHENSIVE INCOME:
Amortization of prior service cost (1)	46	46	93	93
Amortization of net actuarial loss (1)	171	489	344	972
Total recognized in accumulated other comprehensive loss	217	535	437	1,065
Pneumoconiosis benefits
OTHER COMPREHENSIVE INCOME:
Amortization of net actuarial loss (1)	346	259	691	519
Total recognized in accumulated other comprehensive loss	$ 346	$ 259	$ 691	$ 519

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES
CASH FLOWS FROM OPERATING ACTIVITIES	$ 504,023	$ 239,391
Property, plant and equipment:
Capital expenditures	(185,017)	(121,982)
Change in accounts payable and accrued liabilities	(25,630)	8,951
Proceeds from sale of property, plant and equipment	2,468	3,373
Contributions to equity method investments	(1,334)	(20,110)
Purchase of equity securities		(32,639)
JC Resources acquisition	(64,999)
Oil & gas reserve acquisition	(3,935)
Other	833	(935)
Net cash used in investing activities	(277,614)	(163,342)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings under securitization facility		27,500
Payments under securitization facility		(27,500)
Payments on equipment financings	(7,565)	(8,696)
Borrowing under long-term debt	75,000
Payments on long-term debt	(65,474)
Payments on finance lease obligations	(306)	(410)
Payment of debt issuance costs	(11,744)
Payments for purchases of units under unit repurchase program	(19,432)
Payments for tax withholdings related to settlements under deferred compensation plans	(10,334)
Excess purchase price over the contributed basis from JC Resources acquisition	(7,251)
Cash retained by JC Resources in acquisition	(2,933)	(4,074)
Distributions paid to Partners	(182,868)	(78,560)	$ (196,347)
Other	(4,626)	(623)
Net cash used in financing activities	(237,533)	(92,363)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(11,124)	(16,314)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	296,023	122,403	122,403
CASH AND CASH EQUIVALENTS AT END OF PERIOD	284,899	106,089	$ 296,023
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	20,242	17,506
Cash paid for income taxes	5,760	10,964
SUPPLEMENTAL NON-CASH ACTIVITY:
Accounts payable for purchase of property, plant and equipment	18,651	17,276
Right-of-use assets acquired by operating lease	2,280	$ 99
Market value of common units issued under deferred compensation plans before tax withholding requirements	$ 28,906

ORGANIZATION AND PRESENTATION

ORGANIZATION AND PRESENTATION	6 Months Ended
	Jun. 30, 2023
ORGANIZATION AND PRESENTATION
ORGANIZATION AND PRESENTATION	1. ORGANIZATION AND PRESENTATION ​ Significant Relationships Referenced in Notes to Condensed 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, 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. ​ JC Resources Acquisition ​ 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, which was funded with cash on hand ("JC Resources Acquisition"). ​ Basis of Presentation ​ The accompanying condensed consolidated financial statements include the accounts and operations of the ARLP Partnership and present our financial position as of June 30, 2023 and December 31, 2022 and the results of our operations and comprehensive income for the three months ended June 30, 2023 and 2022, and cash flows for the six months ended June 30, 2023 and 2022. All intercompany transactions and accounts have been eliminated. ​ These condensed consolidated financial statements and notes are prepared pursuant to the rules and regulations of the Securities and Exchange Commission for interim reporting and do not include all the information normally included with financial statements prepared in accordance with generally accepted accounting principles ("GAAP") of the United States. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2022. ​ These condensed consolidated financial statements and notes are unaudited. However, in the opinion of management, these condensed consolidated financial statements reflect all normal recurring adjustments necessary for a fair presentation of the results for the periods presented. Results for interim periods are not necessarily indicative of results to be expected for the full year ending December 31, 2023. ​ Use of Estimates ​ The preparation of the ARLP Partnership's condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in our condensed consolidated financial statements. Actual results could differ from those estimates. ​ 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. Management monitors the credit ratings and concentration of risk with these financial institutions on a continuing basis to safeguard cash deposits. Based on this monitoring and other diligence, including discussions with representatives of the financial institutions, we have no reason to believe that any of the financial institutions in which we have deposits in excess of stated federally insured limits are facing financial difficulties, defaults or limited liquidity situations that would cause us to be unable to access to our deposits.

ACQUISITIONS

ACQUISITIONS	6 Months Ended
	Jun. 30, 2023
ACQUISITIONS
ACQUISITIONS	2. ACQUISITION S ​ JC Resources ​ As discussed in Note 1 – Organization and Presentation, 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. ​ Acquisition Agreement ​ On January 27, 2023, we entered into a one-year collaborative agreement with a third party, effective January 1, 2023, committing up to $35.0 million 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. As of June 30, 2023, we have purchased $1.9 million and $2.1 million of oil & gas mineral interests in proved and unproved properties, respectively, pursuant to this agreement. Management fees ​

CONTINGENCIES

CONTINGENCIES	6 Months Ended
	Jun. 30, 2023
CONTINGENCIES
CONTINGENCIES	3. CONTINGENCIES ​ 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 seek class and collective action certification, which we oppose, and the courts have not yet made definitive final rulings on those issues. We had a mediation with the plaintiffs on June 12, 2023 but no settlement was reached. We are defending this litigation vigorously and continue to believe the plaintiffs' claims are without merit. We believe our ultimate exposure, if any, will not be material to our results of operations or financial position; however, if our current belief that the claims are without merit is not upheld, it is reasonably possible that the ultimate resolution of these matters could result in a potential loss that may be material to our results of operations. ​ 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, such matters could have a material adverse effect on our business and operations.

INVENTORIES

INVENTORIES	6 Months Ended
	Jun. 30, 2023
INVENTORIES
INVENTORIES	4. INVENTORIES ​ Inventories consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ ​ ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal ​ $ 66,383 ​ $ 23,553 ​ Supplies (net of reserve for obsolescence of $7,456 and $6,601, respectively) ​ 62,557 ​ 53,773 ​ Total inventories, net ​ $ 128,940 ​ $ 77,326 ​ ​

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	6 Months Ended
	Jun. 30, 2023
FAIR VALUE MEASUREMENTS
FAIR VALUE MEASUREMENTS	5. FAIR VALUE MEASUREMENTS ​ The following table summarizes our fair value measurements within the hierarchy not included elsewhere in these notes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2023 ​ December 31, 2022 ​ ​ Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 ​ ​ (in thousands) ​ Long-term debt ​ $ — ​ $ 429,757 ​ $ — ​ $ — ​ $ 424,420 ​ $ — ​ Total ​ $ — ​ $ 429,757 ​ $ — ​ $ — ​ $ 424,420 ​ $ — ​ ​ 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 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 6 – Long-Term Debt). The fair value of debt, which is based upon these interest rates, is classified as a Level 2 measurement under the fair value hierarchy.

LONG-TERM DEBT

LONG-TERM DEBT	6 Months Ended
	Jun. 30, 2023
LONG-TERM DEBT
LONG-TERM DEBT	6. LONG-TERM DEBT ​ Long-term debt consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unamortized Discount and ​ ​ ​ Principal ​ Debt Issuance Costs ​ ​ ​ June 30, ​ December 31, ​ June 30, ​ December 31, ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Revolving credit facility ​ $ — ​ $ — ​ $ (8,806) ​ $ (2,702) ​ Term loan ​ 70,312 ​ — ​ (1,538) ​ — ​ Senior notes ​ 339,214 ​ 400,000 ​ (1,427) ​ (2,134) ​ Securitization facility ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ November 2019 equipment financing ​ ​ 15,425 ​ ​ 21,072 ​ ​ — ​ ​ — ​ June 2020 equipment financing ​ ​ 4,018 ​ ​ 5,937 ​ ​ — ​ ​ — ​ ​ ​ 428,969 ​ 427,009 ​ (11,771) ​ (4,836) ​ Less current maturities ​ (38,194) ​ (24,970) ​ 423 ​ — ​ Total long-term debt ​ $ 390,775 ​ $ 402,039 ​ $ (11,348) ​ $ (4,836) ​ ​ Credit Facility. ​ The Revolving Credit Facility is underwritten by a syndicate of eighteen financial institutions and the obligations of the lenders are individual obligations, which means the failure of one or more lenders to be able to fund its obligation does not relieve the remaining lenders from funding their obligations. Based on our diligence, including discussions with representatives of certain of these financial institutions, as of June 30, 2023 we have no reason to believe that the banks within our syndicate are facing financial difficulties, defaults or limited liquidity situations that would cause them to be unable to fund their obligations under the Credit Agreement. However, should any of the banks in our syndicate experience conditions in the future that limit their ability to fund their obligations, the amount available under the Revolving Credit Facility could be reduced. ​ 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 term rate 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 and was 0.49% as of June 30, 2023. At June 30, 2023, we had $41.0 million of letters of credit outstanding with $384.0 million available for borrowing under the Revolving Credit Facility. We incurred 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 a minimum fixed charge coverage ratio (as determined in the Credit Agreement) 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 0.10 to 1.0, 0.49 to 1.0 and 145.52 to 1.0, respectively, for the trailing twelve months ended June 30, 2023. We were in compliance with the covenants of the Credit Agreement as of June 30, 2023 and anticipate remaining in compliance with the covenants. ​ Senior Notes. On April 24, 2017, 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 2025 ("Senior Notes") in a private placement to qualified institutional buyers. The Senior Notes have a term of eight years , maturing on May 1, 2025 (the "Term") and accrue interest at an annual rate of 7.5% . Interest is payable semi-annually in arrears on each May 1 and November 1. The indenture governing the 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. During the six months ended June 30, 2023, we repurchased $60.8 million of our Senior Notes. The gain on extinguishment of the Senior Notes is immaterial. In July 2023, we redeemed an additional $50.0 million of our Senior Notes. ​ Accounts Receivable Securitization. ​ November 2019 Equipment Financing. On November 6, 2019, the Intermediate Partnership entered into an equipment financing arrangement accounted for as debt, wherein the Intermediate Partnership received $53.1 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 "November 2019 Equipment Financing"). The November 2019 Equipment Financing contains customary terms and events of default and an implicit interest rate of 4.75% , providing for a four-year term with forty-seven monthly payments of $1.0 million and a balloon payment of $11.6 million upon maturity on November 6, 2023. Upon maturity, the equipment will revert to the Intermediate Partnership. ​ 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 contains customary terms and events of default and provides for forty-eight monthly payments with an implicit interest rate of 6.1% , maturing on June 5, 2024. Upon maturity, the equipment will revert to the Intermediate Partnership.

INCOME TAXES

INCOME TAXES	6 Months Ended
	Jun. 30, 2023
INCOME TAXES
INCOME TAXES	7. INCOME TAXES ​ Components of income tax expense are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 3,935 ​ $ 6,175 ​ $ 8,247 ​ $ 11,209 ​ State ​ 272 ​ 445 ​ 573 ​ 831 ​ ​ ​ 4,207 ​ 6,620 ​ 8,820 ​ 12,040 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (190) ​ (255) ​ (521) ​ 34,665 ​ State ​ (18) ​ (34) ​ (59) ​ 2,341 ​ ​ ​ (208) ​ (289) ​ (580) ​ 37,006 ​ Income tax expense ​ $ 3,999 ​ $ 6,331 ​ $ 8,240 ​ $ 49,046 ​ ​ On March 15, 2022, Alliance Minerals changed its U.S. 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. The Tax Election resulted in the recognition of an initial deferred tax liability of $37.3 million and a corresponding increase to income tax expense for the six months ended June 30, 2022. ​ The effective income tax rate for our income tax expense for the three months ended June 30, 2023 and 2022 and the six months ended June 30, 2023 is 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 six months ended June 30, 2022 is greater than the federal statutory rate, primarily due to the effect of the Tax Election, partially offset by the portion of income not subject to income taxes. ​ Our 2019 through 2022 tax years remain open to examination by tax authorities. We have been notified by the Internal Revenue Service that lower-tier partnership income tax returns for the tax year ended December 31, 2020 have been selected for audit.

VARIABLE INTEREST ENTITIES

VARIABLE INTEREST ENTITIES	6 Months Ended
	Jun. 30, 2023
VARIABLE INTEREST ENTITIES
VARIABLE INTEREST ENTITIES	8. VARIABLE INTEREST ENTITIES ​ Cavalier Minerals ​ On November 10, 2014, our subsidiary, Alliance Minerals, and Bluegrass Minerals Management, LLC ("Bluegrass Minerals") entered into a limited liability company agreement (the "Cavalier Agreement") to create Cavalier Minerals JV, LLC ("Cavalier Minerals"), which was formed to indirectly acquire oil & gas mineral interests through its ownership in AllDale I & II. Alliance Minerals owns a 96% member interest in Cavalier Minerals, and 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. Distributions with respect to Bluegrass Minerals' profits interest are offset by all distributions received by Bluegrass Minerals from the former general partners of AllDale I & II. All members have recovered their investment and Bluegrass Minerals began receiving its profits interest distributions in late 2022. We hold the managing member interest in Cavalier Minerals. ​ We have concluded that Cavalier Minerals is a variable interest entity ("VIE") which we consolidate as the primary beneficiary because we are the managing member and a substantial equity owner in Cavalier Minerals. Bluegrass Minerals' equity ownership of Cavalier Minerals is accounted for as noncontrolling ownership interest in our condensed consolidated balance sheets. In addition, earnings attributable to Bluegrass Minerals are recognized as noncontrolling interest in our condensed consolidated statements of income. ​ AllDale III ​ In February 2017, Alliance Minerals committed to directly invest $30.0 million in AllDale Minerals III, LP ("AllDale III") which was created for similar investment purposes as AllDale I & II. Alliance Minerals completed funding of this commitment in 2018. ​ The AllDale III Partnership Agreement includes a 25% profits interest for the general partner, 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. ​ Since 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 concluded that AllDale III is a VIE. ​ 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 17.8% 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. ​ We have concluded that Francis is a VIE as the 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 as we do not have the power to direct the activities that most significantly impact Francis's economic performance. We account for our ownership interest in the income or loss of Francis as an equity method investment. Following the conversion of our note to preferred equity, we record equity income or loss based on Francis' distribution structure. See Note 9 – Investments for more information. ​ NGP ETP IV ​ On June 2, 2022, we committed to purchase $25.0 million of limited partner interests in NGP ETP IV, L.P. ("NGP ETP 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 ETP IV. As of June 30, 2023, we have funded $5.4 million of this commitment. ​

INVESTMENTS

INVESTMENTS	6 Months Ended
	Jun. 30, 2023
INVESTMENTS
INVESTMENTS	9. INVESTMENT S ​ AllDale III ​ As discussed in Note 8 – Variable Interest Entities, we account for our ownership interest in the income or loss of AllDale III as an equity method investment. We record equity income or loss based on AllDale III's distribution structure. The changes in our equity method investment in AllDale III for each of the periods presented were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 24,695 ​ $ 26,194 ​ $ 25,284 ​ $ 26,325 ​ Equity method investment income ​ ​ 716 ​ ​ 1,585 ​ ​ 1,141 ​ ​ 2,468 ​ Distributions received ​ ​ (960) ​ ​ (1,501) ​ ​ (1,974) ​ ​ (2,515) ​ Ending balance ​ $ 24,451 ​ $ 26,278 ​ $ 24,451 ​ $ 26,278 ​ ​ Francis As discussed in Note 8 – Variable Interest Entities, we account for our ownership interest in the income or loss of Francis as an equity method investment. Prior to the conversion of our convertible note, we did not participate in Francis' earnings or losses; however, upon conversion on April 1, 2023 we began participating. As a development stage company, Francis depends on capital contributions to meet its operating and debt obligations. We currently believe that the carrying value of our investment is recoverable; however, if Francis is unable to raise sufficient funds to continue its operations and meet its debt obligations, it could have an adverse effect on our investment. The changes in our equity method investment in Francis for three and six months ended June 30, 2023 and 2022 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 20,000 ​ $ — ​ $ 20,000 ​ $ — ​ Contributions ​ ​ — ​ ​ 20,000 ​ ​ — ​ ​ 20,000 ​ Equity method investment loss ​ ​ (2,620) ​ ​ — ​ ​ (2,620) ​ ​ — ​ Ending balance ​ $ 17,380 ​ $ 20,000 ​ $ 17,380 ​ $ 20,000 ​ ​ NGP ETP IV ​ As discussed in Note 8 – Variable Interest Entities, we account for our ownership interest in the income or loss of NGP ETP IV as an equity method investment. The changes in our equity method investment in NGP ETP IV for three and six months ended June 30, 2023 and 2022 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 4,254 ​ $ — ​ $ 4,087 ​ $ — ​ Contributions ​ ​ 794 ​ ​ 110 ​ ​ 1,334 ​ ​ 110 ​ Equity method investment loss ​ ​ (90) ​ ​ — ​ ​ (463) ​ ​ — ​ Ending balance ​ $ 4,958 ​ $ 110 ​ $ 4,958 ​ $ 110 ​ ​ Infinitum ​ We hold $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. Our preferred stock provides for non-cumulative dividends when and if declared by Infinitum's board of directors. Each share 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. 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. There have been no fair value adjustments in our investment in Infinitum subsequent to our purchases. During the period we have not observed any price changes that have occurred to identical or similar securities sold by Infinitum that would indicate an adjustment to the fair value of our investment is warranted.

PARTNERS' CAPITAL

PARTNERS' CAPITAL	6 Months Ended
	Jun. 30, 2023
PARTNERS' CAPITAL
PARTNERS' CAPITAL	10. PARTNERS' CAPITAL ​ Distributions ​ Distributions paid or declared during 2022 and 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Payment Date Per Unit Cash Distribution Total Cash Distribution ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ February 14, 2022 ​ $ 0.2500 ​ $ 32,750 ​ May 13, 2022 ​ ​ 0.3500 ​ ​ 45,810 ​ August 12, 2022 ​ ​ 0.4000 ​ ​ 52,338 ​ November 14, 2022 ​ ​ 0.5000 ​ ​ 65,449 ​ Total ​ $ 1.5000 ​ $ 196,347 ​ ​ ​ ​ ​ ​ ​ ​ ​ February 14, 2023 ​ $ 0.7000 ​ $ 91,938 ​ May 15, 2023 ​ ​ 0.7000 ​ ​ 90,930 ​ August 14, 2023 (1) ​ ​ 0.7000 ​ ​ — ​ Total ​ $ 2.1000 ​ $ 182,868 ​ (1) On July 28, 2023, we declared this quarterly distribution payable on August 14, 2023 to all unitholders of record as of August 7, 2023. ​ 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 are authorized to repurchase up to a total of $100.0 million of ARLP common units. During the six months ended June 30, 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. 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. ​ Change in Partners' Capital ​ The following tables present the quarterly change in Partners' Capital for the six months ended June 30, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Limited ​ General ​ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited Partner ​ Partners' ​ Partner's ​ Comprehensive ​ Noncontrolling ​ Total Partners' ​ ​ Units Capital Capital Income (Loss) Interest Capital ​ ​ (in thousands, except unit data) ​ Balance at January 1, 2023 127,195,219 ​ $ 1,656,025 ​ $ 66,548 ​ $ (41,054) ​ $ 26,507 ​ $ 1,708,026 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 189,801 ​ 1,384 ​ — ​ ​ 1,493 192,678 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 565 ​ — 565 ​ Total comprehensive loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 193,243 ​ Settlement of deferred compensation plans ​ 860,060 ​ ​ (9,320) ​ ​ — ​ ​ — ​ ​ — ​ ​ (9,320) ​ Purchase of units under unit repurchase program ​ (860,060) ​ ​ (18,209) ​ ​ — ​ ​ — ​ ​ — ​ ​ (18,209) ​ Common unit-based compensation — ​ 2,830 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,830 ​ Distributions on deferred common unit-based compensation — ​ (2,901) ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,901) ​ Distributions from consolidated company to affiliate noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,288) ​ ​ (2,288) ​ JC Resources acquisition - See Note 1 ​ — ​ ​ (7,251) ​ ​ (64,999) ​ ​ — ​ ​ — ​ ​ (72,250) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (2,933) ​ ​ — ​ ​ — ​ ​ (2,933) ​ Distributions to Partners — ​ ​ (89,037) ​ ​ — ​ ​ — ​ ​ — ​ ​ (89,037) ​ Balance at March 31, 2023 ​ 127,195,219 ​ ​ 1,721,938 ​ ​ — ​ ​ (40,489) ​ ​ 25,712 ​ ​ 1,707,161 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 169,790 ​ — ​ — ​ ​ 1,515 171,305 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 563 ​ — 563 ​ Total comprehensive income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 171,868 ​ Settlement of deferred compensation plans ​ — ​ ​ (1,014) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,014) ​ Purchase of units under unit repurchase program ​ (69,782) ​ ​ (1,223) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,223) ​ Common unit-based compensation — ​ 3,121 ​ ​ — ​ ​ — ​ ​ — ​ ​ 3,121 ​ Distributions on deferred common unit-based compensation — ​ (1,895) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,895) ​ Distributions from consolidated company to noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,226) ​ ​ (2,226) ​ Distributions to Partners — ​ ​ (89,035) ​ ​ — ​ ​ — ​ ​ — ​ ​ (89,035) ​ Balance at June 30, 2023 ​ 127,125,437 ​ $ 1,801,682 ​ $ — ​ $ (39,926) ​ $ 25,001 ​ $ 1,786,757 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Limited ​ General ​ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited Partner ​ Partners' ​ Partner's ​ Comprehensive ​ Noncontrolling ​ Total Partners' ​ ​ Units Capital Capital * Income (Loss) Interest Capital * ​ ​ (in thousands, except unit data) ​ Balance at January 1, 2022 127,195,219 ​ $ 1,279,183 ​ $ 68,075 ​ $ (64,229) ​ $ 11,115 ​ $ 1,294,144 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 36,652 ​ 1,431 ​ — ​ ​ 290 38,373 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 790 ​ — 790 ​ Total comprehensive income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 39,163 ​ Common unit-based compensation — ​ 2,640 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,640 ​ Distributions on deferred common unit-based compensation — ​ (950) ​ ​ — ​ ​ — ​ ​ — ​ ​ (950) ​ Distributions from consolidated company to affiliate noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (298) ​ ​ (298) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (1,590) ​ ​ — ​ ​ — ​ ​ (1,590) ​ Distributions to Partners — ​ ​ (31,800) ​ ​ — ​ ​ — ​ ​ — ​ ​ (31,800) ​ Balance at March 31, 2022 127,195,219 ​ ​ 1,285,725 ​ ​ 67,916 ​ ​ (63,439) ​ ​ 11,107 ​ ​ 1,301,309 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 161,478 ​ 2,050 ​ — ​ ​ 323 163,851 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 794 ​ — 794 ​ Total comprehensive loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 164,645 ​ Common unit-based compensation — ​ 2,340 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,340 ​ Distributions on deferred common unit-based compensation — ​ (1,292) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,292) ​ Distributions from consolidated company to noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (325) ​ ​ (325) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (2,484) ​ ​ — ​ ​ — ​ ​ (2,484) ​ Distributions to Partners — ​ ​ (44,518) ​ ​ — ​ ​ — ​ ​ — ​ ​ (44,518) ​ Balance at June 30, 2022 127,195,219 ​ $ 1,403,733 ​ $ 67,482 ​ $ (62,645) ​ $ 11,105 ​ $ 1,419,675 ​ *

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	6 Months Ended
	Jun. 30, 2023
REVENUE FROM CONTRACTS WITH CUSTOMERS
REVENUE FROM CONTRACTS WITH CUSTOMERS	11. 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 16 – Segment Information. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ Other, ​ ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ Corporate and ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal Elimination Consolidated ​ ​ ​ (in thousands) ​ Three Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 331,813 ​ $ 228,518 ​ $ — ​ $ — ​ $ — ​ $ 560,331 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 33,087 ​ ​ — ​ ​ — ​ ​ 33,087 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 16,567 ​ ​ (16,567) ​ ​ — ​ Transportation revenues ​ ​ 21,178 ​ ​ 9,349 ​ ​ — ​ ​ — ​ ​ — ​ ​ 30,527 ​ Other revenues ​ ​ 2,401 ​ ​ 375 ​ ​ 325 ​ ​ — ​ ​ 14,790 ​ ​ 17,891 ​ Total revenues ​ $ 355,392 ​ $ 238,242 ​ $ 33,412 ​ $ 16,567 ​ $ (1,777) ​ $ 641,836 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 290,389 ​ $ 241,418 ​ $ — ​ $ — ​ $ — ​ $ 531,807 ​ Oil & gas royalties * ​ ​ — ​ ​ — ​ ​ 39,287 ​ ​ — ​ ​ — ​ ​ 39,287 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 14,525 ​ ​ (14,525) ​ ​ — ​ Transportation revenues ​ ​ 21,449 ​ ​ 13,936 ​ ​ — ​ ​ — ​ ​ — ​ ​ 35,385 ​ Other revenues ​ ​ 1,659 ​ ​ 328 ​ ​ 669 ​ ​ — ​ ​ 10,743 ​ ​ 13,399 ​ Total revenues ​ $ 313,497 ​ $ 255,682 ​ $ 39,956 ​ $ 14,525 ​ $ (3,782) ​ $ 619,878 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 668,723 ​ $ 470,392 ​ $ — ​ $ — ​ $ — ​ $ 1,139,115 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 67,584 ​ ​ — ​ ​ — ​ ​ 67,584 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 32,080 ​ ​ (32,080) ​ ​ — ​ Transportation revenues ​ ​ 42,506 ​ ​ 18,259 ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,765 ​ Other revenues ​ ​ 4,569 ​ ​ 850 ​ ​ 1,365 ​ ​ — ​ ​ 30,510 ​ ​ 37,294 ​ Total revenues ​ $ 715,798 ​ $ 489,501 ​ $ 68,949 ​ $ 32,080 ​ $ (1,570) ​ $ 1,304,758 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 544,294 ​ $ 375,873 ​ $ — ​ $ — ​ $ — ​ $ 920,167 ​ Oil & gas royalties * ​ ​ — ​ ​ — ​ ​ 72,683 ​ ​ — ​ ​ — ​ ​ 72,683 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 29,692 ​ ​ (29,692) ​ ​ — ​ Transportation revenues ​ ​ 40,340 ​ ​ 24,417 ​ ​ — ​ ​ — ​ ​ — ​ ​ 64,757 ​ Other revenues ​ ​ 3,559 ​ ​ 691 ​ ​ 793 ​ ​ — ​ ​ 20,650 ​ ​ 25,693 ​ Total revenues ​ $ 588,193 ​ $ 400,981 ​ $ 73,476 ​ $ 29,692 ​ $ (9,042) ​ $ 1,083,300 ​ * Recast as discussed in Note 1 – Organization and Presentation. ​ The following table illustrates the amount of our transaction price for all current coal supply contracts allocated to performance obligations that are unsatisfied or partially unsatisfied as of June 30, 2023 and disaggregated by segment and contract duration. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2026 and ​ ​ ​ 2023 2024 2025 Thereafter Total ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Illinois Basin Coal Operations coal revenues ​ $ 762,478 ​ $ 925,042 ​ $ 344,601 ​ $ 243,600 ​ $ 2,275,721 Appalachia Coal Operations coal revenues ​ ​ 452,387 ​ ​ 574,481 ​ ​ 325,425 ​ ​ 1,600 ​ ​ 1,353,893 Total coal revenues (1) ​ $ 1,214,865 ​ $ 1,499,523 ​ $ 670,026 ​ $ 245,200 ​ $ 3,629,614 (1) Coal revenues generally consists of consolidated revenues excluding our Oil & Gas Royalties segment as well as intercompany revenues from our Coal Royalties segment .

EARNINGS PER LIMITED PARTNER UN

EARNINGS PER LIMITED PARTNER UNIT	6 Months Ended
	Jun. 30, 2023
EARNINGS PER LIMITED PARTNER UNIT
EARNINGS PER LIMITED PARTNER UNIT	12 . 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, which is discussed in more detail in Note 1 – Organization and Presentation, 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 are 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 Long-Term Incentive Plan ("LTIP") and phantom units in notional accounts under our Supplemental Executive Retirement Plan ("SERP") and the MGP Amended and Restated Deferred Compensation Plan for Directors ("Directors' Deferred Compensation Plan"). ​ 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 for the three and six months ended June 30, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 (1) ​ ​ (in thousands, except per unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP ​ $ 169,790 ​ $ 163,528 ​ $ 360,975 ​ $ 201,611 ​ Adjustment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ General partner's interest in net income attributable to ARLP ​ — ​ (2,050) ​ (1,384) ​ (3,481) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited partners' interest in net income attributable to ARLP ​ 169,790 ​ 161,478 ​ 359,591 ​ 198,130 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Distributions to participating securities ​ (2,396) ​ (1,720) ​ (4,828) ​ (3,272) ​ Undistributed earnings attributable to participating securities ​ (2,071) ​ (3,645) ​ (4,981) ​ (3,245) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP available to limited partners ​ $ 165,323 ​ $ 156,113 ​ $ 349,782 ​ $ 191,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average limited partner units outstanding – basic and diluted ​ 127,183 ​ 127,195 ​ 127,236 ​ 127,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per limited partner unit - basic and diluted (2) ​ $ 1.30 ​ $ 1.23 ​ $ 2.75 ​ $ 1.51 ​ (1) Recast as discussed in Note 1 – Organization and Presentation. (2) 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. The combined total of LTIP, SERP and Directors' Deferred Compensation Plan units of 2,577 and 2,896 for the three and six months ended June 30, 2023, respectively, and 3,529 and 3,289 for the three and six months ended June 30, 2022, respectively, were considered anti-dilutive under the treasury stock method .

WORKERS' COMPENSATION AND PNEUM

WORKERS' COMPENSATION AND PNEUMOCONIOSIS	6 Months Ended
	Jun. 30, 2023
WORKERS' COMPENSATION AND PNEUMOCONIOSIS
WORKERS' COMPENSATION AND PNEUMOCONIOSIS	13. WORKERS' COMPENSATION AND PNEUMOCONIOSIS ​ The changes in the workers' compensation liability, including current and long-term liability balances, for each of the periods presented were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 50,017 ​ $ 53,206 ​ $ 49,452 ​ $ 53,448 ​ Changes in accruals ​ 2,196 ​ 2,271 ​ 6,070 ​ 4,546 ​ Payments ​ (2,646) ​ (3,278) ​ (6,505) ​ (6,082) ​ Interest accretion ​ 551 ​ 287 ​ 1,101 ​ 574 ​ Valuation loss (gain) (1) ​ 990 ​ (5,265) ​ 990 ​ (5,265) ​ Ending balance ​ $ 51,108 ​ $ 47,221 ​ $ 51,108 ​ $ 47,221 ​ (1) Our estimate of the liability for the present value of current workers′ compensation benefits is based on our actuarial calculations. Our actuarial calculations are based on a blend of actuarial projection methods and numerous assumptions including claims development patterns, mortality, medical costs and interest rates. The valuation loss in 2023 is due to adverse claims development. The valuation gain in 2022 is due to an increase in the discount rate from 2.41% on December 31, 2021 to 4.22% on June 30, 2022. ​ We limit our exposure to traumatic injury claims by purchasing a high deductible insurance policy that starts paying benefits after deductibles for a claim have been met. The deductible level may vary by claim year. 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 June 30, 2023 are $4.1 million and are included in Other long-term assets ​ Certain of our mine operating entities are liable under state statutes and the Federal Coal Mine Health and Safety Act of 1969, as amended, to pay pneumoconiosis, or black lung, benefits to eligible employees and former employees and their dependents. Components of the net periodic benefit cost for each of the periods presented are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Service cost ​ $ 675 ​ $ 954 ​ $ 1,344 ​ $ 1,901 Interest cost (1) ​ 1,238 ​ 749 ​ 2,476 ​ 1,496 ​ Net amortization (1) ​ 346 ​ 259 ​ 691 ​ 519 ​ Net periodic benefit cost ​ $ 2,259 ​ $ 1,962 ​ $ 4,511 ​ $ 3,916 ​ (1) Interest cost and net amortization are included in the Other income (expense) line item within our condensed consolidated statements of income.

COMMON UNIT-BASED COMPENSATION

COMMON UNIT-BASED COMPENSATION PLANS	6 Months Ended
	Jun. 30, 2023
COMMON UNIT-BASED COMPENSATION PLANS
COMMON UNIT-BASED COMPENSATION PLANS	14. COMMON UNIT-BASED COMPENSATION PLANS ​ Long-Term Incentive Plan ​ A summary of non-vested LTIP grants as of and for the six months ended June 30, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average grant date fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-vested grants at January 1, 2023 ​ 3,697,133 ​ $ 7.40 ​ ​ 75,126 ​ Granted (1) 447,225 ​ ​ 21.54 ​ ​ ​ ​ Vested (2) (1,291,330) ​ 5.02 ​ ​ ​ ​ Forfeited (145,584) ​ 6.86 ​ ​ ​ ​ Non-vested grants at June 30, 2023 2,707,444 ​ 10.90 ​ ​ 50,061 ​ (1) The restricted units granted during 2023 have certain minimum-value guarantees per unit, regardless of whether or not the awards vest. (2) During the six months ended June 30, 2023, we issued 860,060 unrestricted common units to the LTIP participants. The remaining vested units were settled in cash to satisfy tax withholding obligations of the LTIP participants. ​ LTIP expense for grants of restricted units was $2.7 million and $ 2.1 million for the three months ended June 30, 2023 and 2022, respectively, and $4.9 million and $4.4 million for the six months ended June 30, 2023 and 2022, respectively. The total obligation associated with LTIP grants of restricted units as of June 30, 2023 was $ 14.1 million and is included in the partners' capital Limited partners-common unitholders line item in our condensed consolidated balance sheets. As of June 30, 2023, there was $15.4 million in total unrecognized compensation expense related to the non-vested LTIP restricted unit grants that are expected to vest. That expense is expected to be recognized over a weighted-average period of 1.1 years. ​ Supplemental Executive Retirement Plan and Directors' Deferred Compensation Plan ​ A summary of SERP and Directors' Deferred Compensation Plan activity as of and for the six months ended June 30, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average grant date fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Phantom units outstanding as of January 1, 2023 ​ 742,540 ​ $ 20.28 ​ $ 15,088 ​ Granted ​ 49,480 ​ ​ 19.72 ​ ​ ​ ​ Settled (1) (49,331) ​ ​ 20.27 ​ ​ ​ ​ Phantom units outstanding as of June 30, 2023 742,689 ​ 20.38 ​ ​ 13,732 ​ (1) During the six months ended June 30, 2023, we purchased 27,576 ARLP common units on the open market to settle the account of a participant under the SERP. Units purchased and delivered to the participant were net of units settled in cash to satisfy tax withholding obligations. ​ Total SERP and Directors' Deferred Compensation Plan expense was $0.6 million and $0.3 million for the three months ended June 30, 2023 and 2022, respectively, and $1.2 million and $0.6 million for the six months ended June 30, 2023 and 2022, respectively. As of June 30, 2023, the total obligation associated with the SERP and Directors' Deferred Compensation Plan was $15.1 million and is included in the partners' capital Limited partners-common unitholders

COMPONENTS OF PENSION PLAN NET

COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS	6 Months Ended
	Jun. 30, 2023
COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS
COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS	15. COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS ​ Eligible employees at certain of our mining operations participate in a defined benefit plan (the "Pension Plan") that we sponsor. The Pension Plan is currently closed to new applicants and 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. Components of the net periodic benefit cost for each of the periods presented are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Interest cost ​ $ 1,296 ​ $ 936 ​ $ 2,591 ​ $ 1,868 ​ Expected return on plan assets ​ (1,517) ​ (1,664) ​ (3,115) ​ (3,329) ​ Amortization of prior service cost ​ ​ 46 ​ ​ 46 ​ ​ 93 ​ ​ 93 ​ Amortization of net loss ​ 171 ​ 489 ​ 344 ​ 972 ​ Net periodic benefit credit (1) ​ $ (4) ​ $ (193) ​ $ (87) ​ $ (396) ​ (1) Net periodic benefit credit for the Pension Plan is included in the Other income (expense) line item within our condensed consolidated statements of income. ​ As a result of certain pension plan relief provided by the American Rescue Plan Act enacted in March 2021, we do not expect to make contributions to the Pension Plan during 2023.

SEGMENT INFORMATION

SEGMENT INFORMATION	6 Months Ended
	Jun. 30, 2023
SEGMENT INFORMATION
SEGMENT INFORMATION	16. 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, metallurgical and industrial users as well as royalty income from oil & gas mineral interests. In addition, we continue to position ourselves as a reliable energy partner for the future as we pursue opportunities that support the advancement of energy and related infrastructure. 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 mining complex, (b) the Warrior mining complex, (c) the River View mining complex and (d) the Hamilton mining complex. The segment also includes our Mt. Vernon Transfer Terminal, LLC ("Mt. Vernon") 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 AR Midland, LP ("AR Midland") and AllDale I & II and includes Alliance Minerals' equity interests in both AllDale III (Note 9 – Investments) and Cavalier Minerals. ​ The 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 two-thirds 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, Matrix Design Group, LLC, its subsidiaries, and Alliance Design Group, LLC (collectively referred to as the "Matrix Group"), our investments in Francis, Infinitum and NGP ETP IV (see Note 9 – Investments), Wildcat Insurance, which assists the ARLP Partnership with its insurance requirements, AROP Funding and Alliance Finance (both discussed in Note 6 – Long-Term Debt) and other miscellaneous activities. 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 ​ Other, ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ ​ Corporate and ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal ​ Elimination Consolidated ​ ​ (in thousands) Three Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 355,392 ​ $ 238,242 ​ $ 33,412 ​ $ — ​ $ 14,790 ​ $ 641,836 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 16,567 ​ ​ (16,567) ​ ​ — ​ Total revenues (2) ​ ​ 355,392 ​ ​ 238,242 ​ ​ 33,412 ​ ​ 16,567 ​ ​ (1,777) ​ ​ 641,836 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (3) ​ 214,666 ​ 119,319 ​ 3,562 ​ 5,597 ​ (4,710) ​ 338,434 ​ Segment Adjusted EBITDA (4) ​ 119,551 ​ 109,573 ​ 29,050 ​ 10,970 ​ 222 ​ 269,366 ​ Capital expenditures (5) ​ 57,469 ​ 31,309 ​ 40 ​ — ​ 725 ​ 89,543 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside (1) ​ $ 313,497 ​ $ 255,682 ​ $ 39,956 ​ $ — ​ $ 10,743 ​ $ 619,878 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 14,525 ​ ​ (14,525) ​ ​ — ​ Total revenues (2) ​ ​ 313,497 ​ ​ 255,682 ​ ​ 39,956 ​ ​ 14,525 ​ ​ (3,782) ​ ​ 619,878 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (1) (3) ​ 194,697 ​ 117,369 ​ 3,582 ​ 5,398 ​ (4,624) ​ 316,422 ​ Segment Adjusted EBITDA (1) (4) ​ 97,352 ​ 124,377 ​ 37,638 ​ 9,127 ​ 839 ​ 269,333 ​ Capital expenditures ​ 35,343 ​ 22,491 ​ — ​ — ​ 4,995 ​ 62,829 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 715,798 ​ $ 489,501 ​ $ 68,949 ​ $ — ​ $ 30,510 ​ $ 1,304,758 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 32,080 ​ ​ (32,080) ​ ​ — ​ Total revenues (2) ​ ​ 715,798 ​ ​ 489,501 ​ ​ 68,949 ​ ​ 32,080 ​ ​ (1,570) ​ ​ 1,304,758 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (3) ​ 421,735 ​ ​ 245,118 ​ ​ 7,986 ​ ​ 10,985 ​ ​ (8,094) ​ 677,730 ​ Segment Adjusted EBITDA (4) ​ 251,559 ​ ​ 226,123 ​ ​ 59,095 ​ ​ 21,095 ​ ​ 3,441 ​ 561,313 ​ Total assets ​ 830,821 ​ ​ 470,929 ​ ​ 758,816 ​ ​ 322,926 ​ ​ 404,451 ​ 2,787,943 ​ Capital expenditures (5) ​ 119,451 ​ ​ 63,814 ​ ​ 42 ​ ​ 400 ​ ​ 1,310 ​ 185,017 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside (1) ​ $ 588,193 ​ $ 400,981 ​ $ 73,476 ​ $ — ​ $ 20,650 ​ $ 1,083,300 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 29,692 ​ ​ (29,692) ​ ​ — ​ Total revenues (2) ​ ​ 588,193 ​ ​ 400,981 ​ ​ 73,476 ​ ​ 29,692 ​ ​ (9,042) ​ ​ 1,083,300 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (1) (3) ​ 372,286 ​ ​ 201,084 ​ ​ 6,859 ​ ​ 10,217 ​ ​ (12,568) ​ 577,878 ​ Segment Adjusted EBITDA (1) (4) ​ 175,567 ​ ​ 175,480 ​ ​ 68,473 ​ ​ 19,475 ​ ​ 3,525 ​ 442,520 ​ Total assets (1) ​ 748,291 ​ ​ 457,724 ​ ​ 734,760 ​ ​ 288,509 ​ ​ 171,389 ​ 2,400,673 ​ Capital expenditures ​ 71,890 ​ ​ 40,836 ​ ​ — ​ ​ — ​ ​ 9,256 ​ 121,982 ​ (1) Recast for the JC Resources Acquisition as discussed in Note 1 – Organization and Presentation. (2) Revenues included in the Other, Corporate and Elimination column are attributable to intercompany eliminations, which are primarily intercompany coal royalty eliminations, outside revenues at the Matrix Group and other outside miscellaneous sales and revenue activities. ​ (3) Segment Adjusted EBITDA Expense includes operating expenses, coal purchases, if applicable, and other income. Transportation expenses are excluded as transportation revenues are recognized in an amount equal to transportation expenses when title passes to the customer. ​ ​ The following is a reconciliation of consolidated Segment Adjusted EBITDA Expense to Operating expenses (excluding depreciation, depletion and amortization) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Operating expenses (excluding depreciation, depletion and amortization) ​ $ 334,402 ​ $ 316,850 ​ $ 673,125 ​ $ 578,873 ​ Outside coal purchases ​ 4,209 ​ 151 ​ 4,209 ​ 151 ​ Other expense (income) ​ (177) ​ (579) ​ 396 ​ (1,146) ​ Segment Adjusted EBITDA Expense ​ $ 338,434 ​ $ 316,422 ​ $ 677,730 ​ $ 577,878 ​ ​ (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. Management therefore is able 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. Consolidated Segment Adjusted EBITDA is reconciled to net income as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Net income ​ $ 171,305 ​ $ 163,851 ​ $ 363,983 ​ $ 202,224 ​ Noncontrolling interest ​ ​ (1,515) ​ ​ (323) ​ ​ (3,008) ​ ​ (613) ​ Net income attributable to ARLP ​ $ 169,790 ​ $ 163,528 ​ $ 360,975 ​ $ 201,611 ​ General and administrative ​ 20,130 ​ 22,480 ​ 41,215 ​ 41,102 ​ Depreciation, depletion and amortization ​ 68,639 ​ 67,690 ​ 134,189 ​ 131,830 ​ Interest expense, net ​ 6,808 ​ 9,304 ​ 16,694 ​ 18,931 ​ Income tax expense ​ 3,999 ​ 6,331 ​ 8,240 ​ 49,046 ​ Consolidated Segment Adjusted EBITDA ​ $ 269,366 ​ $ 269,333 ​ $ 561,313 ​ $ 442,520 ​ ​ (5) Capital expenditures for the three and six months ended June 30, 2023 exclude $1.1 million and $3.9 million, respectively, paid towards the Acquisition Agreement. Capital expenditures for the six months ended June 30, 2023 also exclude the $72.3 million paid for the JC Resources Acquisition (See Note 2 – Acquisitions) .

ORGANIZATION AND PRESENTATION (

ORGANIZATION AND PRESENTATION (Policies)	6 Months Ended
	Jun. 30, 2023
ORGANIZATION AND PRESENTATION
Consolidation	Significant Relationships Referenced in Notes to Condensed 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, 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.
JC Resources Acquisition	JC Resources Acquisition ​ 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, which was funded with cash on hand ("JC Resources Acquisition").
Basis of Presentation	Basis of Presentation ​ The accompanying condensed consolidated financial statements include the accounts and operations of the ARLP Partnership and present our financial position as of June 30, 2023 and December 31, 2022 and the results of our operations and comprehensive income for the three months ended June 30, 2023 and 2022, and cash flows for the six months ended June 30, 2023 and 2022. All intercompany transactions and accounts have been eliminated. ​ These condensed consolidated financial statements and notes are prepared pursuant to the rules and regulations of the Securities and Exchange Commission for interim reporting and do not include all the information normally included with financial statements prepared in accordance with generally accepted accounting principles ("GAAP") of the United States. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2022. ​ These condensed consolidated financial statements and notes are unaudited. However, in the opinion of management, these condensed consolidated financial statements reflect all normal recurring adjustments necessary for a fair presentation of the results for the periods presented. Results for interim periods are not necessarily indicative of results to be expected for the full year ending December 31, 2023.
Use of Estimates	Use of Estimates ​ The preparation of the ARLP Partnership's condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in our condensed consolidated financial statements. Actual results could differ from those estimates.
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. Management monitors the credit ratings and concentration of risk with these financial institutions on a continuing basis to safeguard cash deposits. Based on this monitoring and other diligence, including discussions with representatives of the financial institutions, we have no reason to believe that any of the financial institutions in which we have deposits in excess of stated federally insured limits are facing financial difficulties, defaults or limited liquidity situations that would cause us to be unable to access to our deposits.

INVENTORIES (Tables)

INVENTORIES (Tables)	6 Months Ended
	Jun. 30, 2023
INVENTORIES
Schedule of inventories	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ ​ ​ 2023 2022 ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal ​ $ 66,383 ​ $ 23,553 ​ Supplies (net of reserve for obsolescence of $7,456 and $6,601, respectively) ​ 62,557 ​ 53,773 ​ Total inventories, net ​ $ 128,940 ​ $ 77,326 ​

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	6 Months Ended
	Jun. 30, 2023
FAIR VALUE MEASUREMENTS
Summary of fair value measurements within the hierarchy	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2023 ​ December 31, 2022 ​ ​ Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 ​ ​ (in thousands) ​ Long-term debt ​ $ — ​ $ 429,757 ​ $ — ​ $ — ​ $ 424,420 ​ $ — ​ Total ​ $ — ​ $ 429,757 ​ $ — ​ $ — ​ $ 424,420 ​ $ — ​

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	6 Months Ended
	Jun. 30, 2023
LONG-TERM DEBT
Schedule of long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unamortized Discount and ​ ​ ​ Principal ​ Debt Issuance Costs ​ ​ ​ June 30, ​ December 31, ​ June 30, ​ December 31, ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Revolving credit facility ​ $ — ​ $ — ​ $ (8,806) ​ $ (2,702) ​ Term loan ​ 70,312 ​ — ​ (1,538) ​ — ​ Senior notes ​ 339,214 ​ 400,000 ​ (1,427) ​ (2,134) ​ Securitization facility ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ November 2019 equipment financing ​ ​ 15,425 ​ ​ 21,072 ​ ​ — ​ ​ — ​ June 2020 equipment financing ​ ​ 4,018 ​ ​ 5,937 ​ ​ — ​ ​ — ​ ​ ​ 428,969 ​ 427,009 ​ (11,771) ​ (4,836) ​ Less current maturities ​ (38,194) ​ (24,970) ​ 423 ​ — ​ Total long-term debt ​ $ 390,775 ​ $ 402,039 ​ $ (11,348) ​ $ (4,836) ​

INCOME TAXES (Tables)

INCOME TAXES (Tables)	6 Months Ended
	Jun. 30, 2023
INCOME TAXES
Components of income tax expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 3,935 ​ $ 6,175 ​ $ 8,247 ​ $ 11,209 ​ State ​ 272 ​ 445 ​ 573 ​ 831 ​ ​ ​ 4,207 ​ 6,620 ​ 8,820 ​ 12,040 ​ Deferred: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ (190) ​ (255) ​ (521) ​ 34,665 ​ State ​ (18) ​ (34) ​ (59) ​ 2,341 ​ ​ ​ (208) ​ (289) ​ (580) ​ 37,006 ​ Income tax expense ​ $ 3,999 ​ $ 6,331 ​ $ 8,240 ​ $ 49,046 ​

INVESTMENTS (Tables)

INVESTMENTS (Tables)	6 Months Ended
	Jun. 30, 2023
All Dale Minerals III
INVESTMENTS
Schedule of changes in equity method investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 24,695 ​ $ 26,194 ​ $ 25,284 ​ $ 26,325 ​ Equity method investment income ​ ​ 716 ​ ​ 1,585 ​ ​ 1,141 ​ ​ 2,468 ​ Distributions received ​ ​ (960) ​ ​ (1,501) ​ ​ (1,974) ​ ​ (2,515) ​ Ending balance ​ $ 24,451 ​ $ 26,278 ​ $ 24,451 ​ $ 26,278 ​
Francis Renewable Energy
INVESTMENTS
Schedule of changes in equity method investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 20,000 ​ $ — ​ $ 20,000 ​ $ — ​ Contributions ​ ​ — ​ ​ 20,000 ​ ​ — ​ ​ 20,000 ​ Equity method investment loss ​ ​ (2,620) ​ ​ — ​ ​ (2,620) ​ ​ — ​ Ending balance ​ $ 17,380 ​ $ 20,000 ​ $ 17,380 ​ $ 20,000 ​
NGP ETP
INVESTMENTS
Schedule of changes in equity method investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 4,254 ​ $ — ​ $ 4,087 ​ $ — ​ Contributions ​ ​ 794 ​ ​ 110 ​ ​ 1,334 ​ ​ 110 ​ Equity method investment loss ​ ​ (90) ​ ​ — ​ ​ (463) ​ ​ — ​ Ending balance ​ $ 4,958 ​ $ 110 ​ $ 4,958 ​ $ 110 ​

PARTNERS' CAPITAL (Tables)

PARTNERS' CAPITAL (Tables)	6 Months Ended
	Jun. 30, 2023
PARTNERS' CAPITAL
Summary of quarterly per unit distribution paid	​ ​ ​ ​ ​ ​ ​ ​ Payment Date Per Unit Cash Distribution Total Cash Distribution ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ February 14, 2022 ​ $ 0.2500 ​ $ 32,750 ​ May 13, 2022 ​ ​ 0.3500 ​ ​ 45,810 ​ August 12, 2022 ​ ​ 0.4000 ​ ​ 52,338 ​ November 14, 2022 ​ ​ 0.5000 ​ ​ 65,449 ​ Total ​ $ 1.5000 ​ $ 196,347 ​ ​ ​ ​ ​ ​ ​ ​ ​ February 14, 2023 ​ $ 0.7000 ​ $ 91,938 ​ May 15, 2023 ​ ​ 0.7000 ​ ​ 90,930 ​ August 14, 2023 (1) ​ ​ 0.7000 ​ ​ — ​ Total ​ $ 2.1000 ​ $ 182,868 ​ (1) On July 28, 2023, we declared this quarterly distribution payable on August 14, 2023 to all unitholders of record as of August 7, 2023.
Summary of changes to Partners' Capital	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Limited ​ General ​ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited Partner ​ Partners' ​ Partner's ​ Comprehensive ​ Noncontrolling ​ Total Partners' ​ ​ Units Capital Capital Income (Loss) Interest Capital ​ ​ (in thousands, except unit data) ​ Balance at January 1, 2023 127,195,219 ​ $ 1,656,025 ​ $ 66,548 ​ $ (41,054) ​ $ 26,507 ​ $ 1,708,026 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 189,801 ​ 1,384 ​ — ​ ​ 1,493 192,678 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 565 ​ — 565 ​ Total comprehensive loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 193,243 ​ Settlement of deferred compensation plans ​ 860,060 ​ ​ (9,320) ​ ​ — ​ ​ — ​ ​ — ​ ​ (9,320) ​ Purchase of units under unit repurchase program ​ (860,060) ​ ​ (18,209) ​ ​ — ​ ​ — ​ ​ — ​ ​ (18,209) ​ Common unit-based compensation — ​ 2,830 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,830 ​ Distributions on deferred common unit-based compensation — ​ (2,901) ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,901) ​ Distributions from consolidated company to affiliate noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,288) ​ ​ (2,288) ​ JC Resources acquisition - See Note 1 ​ — ​ ​ (7,251) ​ ​ (64,999) ​ ​ — ​ ​ — ​ ​ (72,250) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (2,933) ​ ​ — ​ ​ — ​ ​ (2,933) ​ Distributions to Partners — ​ ​ (89,037) ​ ​ — ​ ​ — ​ ​ — ​ ​ (89,037) ​ Balance at March 31, 2023 ​ 127,195,219 ​ ​ 1,721,938 ​ ​ — ​ ​ (40,489) ​ ​ 25,712 ​ ​ 1,707,161 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 169,790 ​ — ​ — ​ ​ 1,515 171,305 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 563 ​ — 563 ​ Total comprehensive income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 171,868 ​ Settlement of deferred compensation plans ​ — ​ ​ (1,014) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,014) ​ Purchase of units under unit repurchase program ​ (69,782) ​ ​ (1,223) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,223) ​ Common unit-based compensation — ​ 3,121 ​ ​ — ​ ​ — ​ ​ — ​ ​ 3,121 ​ Distributions on deferred common unit-based compensation — ​ (1,895) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,895) ​ Distributions from consolidated company to noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,226) ​ ​ (2,226) ​ Distributions to Partners — ​ ​ (89,035) ​ ​ — ​ ​ — ​ ​ — ​ ​ (89,035) ​ Balance at June 30, 2023 ​ 127,125,437 ​ $ 1,801,682 ​ $ — ​ $ (39,926) ​ $ 25,001 ​ $ 1,786,757 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Limited ​ General ​ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited Partner ​ Partners' ​ Partner's ​ Comprehensive ​ Noncontrolling ​ Total Partners' ​ ​ Units Capital Capital * Income (Loss) Interest Capital * ​ ​ (in thousands, except unit data) ​ Balance at January 1, 2022 127,195,219 ​ $ 1,279,183 ​ $ 68,075 ​ $ (64,229) ​ $ 11,115 ​ $ 1,294,144 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 36,652 ​ 1,431 ​ — ​ ​ 290 38,373 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 790 ​ — 790 ​ Total comprehensive income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 39,163 ​ Common unit-based compensation — ​ 2,640 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,640 ​ Distributions on deferred common unit-based compensation — ​ (950) ​ ​ — ​ ​ — ​ ​ — ​ ​ (950) ​ Distributions from consolidated company to affiliate noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (298) ​ ​ (298) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (1,590) ​ ​ — ​ ​ — ​ ​ (1,590) ​ Distributions to Partners — ​ ​ (31,800) ​ ​ — ​ ​ — ​ ​ — ​ ​ (31,800) ​ Balance at March 31, 2022 127,195,219 ​ ​ 1,285,725 ​ ​ 67,916 ​ ​ (63,439) ​ ​ 11,107 ​ ​ 1,301,309 ​ Comprehensive income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income — ​ 161,478 ​ 2,050 ​ — ​ ​ 323 163,851 ​ Actuarially determined long-term liability adjustments — ​ — ​ — ​ 794 ​ — 794 ​ Total comprehensive loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 164,645 ​ Common unit-based compensation — ​ 2,340 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,340 ​ Distributions on deferred common unit-based compensation — ​ (1,292) ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,292) ​ Distributions from consolidated company to noncontrolling interest ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (325) ​ ​ (325) ​ Cash retained by JC Resources in acquisition - See Note 1 ​ — ​ ​ — ​ ​ (2,484) ​ ​ — ​ ​ — ​ ​ (2,484) ​ Distributions to Partners — ​ ​ (44,518) ​ ​ — ​ ​ — ​ ​ — ​ ​ (44,518) ​ Balance at June 30, 2022 127,195,219 ​ $ 1,403,733 ​ $ 67,482 ​ $ (62,645) ​ $ 11,105 ​ $ 1,419,675 ​ *

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables)	6 Months Ended
	Jun. 30, 2023
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) ​ Three Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 331,813 ​ $ 228,518 ​ $ — ​ $ — ​ $ — ​ $ 560,331 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 33,087 ​ ​ — ​ ​ — ​ ​ 33,087 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 16,567 ​ ​ (16,567) ​ ​ — ​ Transportation revenues ​ ​ 21,178 ​ ​ 9,349 ​ ​ — ​ ​ — ​ ​ — ​ ​ 30,527 ​ Other revenues ​ ​ 2,401 ​ ​ 375 ​ ​ 325 ​ ​ — ​ ​ 14,790 ​ ​ 17,891 ​ Total revenues ​ $ 355,392 ​ $ 238,242 ​ $ 33,412 ​ $ 16,567 ​ $ (1,777) ​ $ 641,836 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 290,389 ​ $ 241,418 ​ $ — ​ $ — ​ $ — ​ $ 531,807 ​ Oil & gas royalties * ​ ​ — ​ ​ — ​ ​ 39,287 ​ ​ — ​ ​ — ​ ​ 39,287 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 14,525 ​ ​ (14,525) ​ ​ — ​ Transportation revenues ​ ​ 21,449 ​ ​ 13,936 ​ ​ — ​ ​ — ​ ​ — ​ ​ 35,385 ​ Other revenues ​ ​ 1,659 ​ ​ 328 ​ ​ 669 ​ ​ — ​ ​ 10,743 ​ ​ 13,399 ​ Total revenues ​ $ 313,497 ​ $ 255,682 ​ $ 39,956 ​ $ 14,525 ​ $ (3,782) ​ $ 619,878 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 668,723 ​ $ 470,392 ​ $ — ​ $ — ​ $ — ​ $ 1,139,115 ​ Oil & gas royalties ​ ​ — ​ ​ — ​ ​ 67,584 ​ ​ — ​ ​ — ​ ​ 67,584 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 32,080 ​ ​ (32,080) ​ ​ — ​ Transportation revenues ​ ​ 42,506 ​ ​ 18,259 ​ ​ — ​ ​ — ​ ​ — ​ ​ 60,765 ​ Other revenues ​ ​ 4,569 ​ ​ 850 ​ ​ 1,365 ​ ​ — ​ ​ 30,510 ​ ​ 37,294 ​ Total revenues ​ $ 715,798 ​ $ 489,501 ​ $ 68,949 ​ $ 32,080 ​ $ (1,570) ​ $ 1,304,758 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal sales ​ $ 544,294 ​ $ 375,873 ​ $ — ​ $ — ​ $ — ​ $ 920,167 ​ Oil & gas royalties * ​ ​ — ​ ​ — ​ ​ 72,683 ​ ​ — ​ ​ — ​ ​ 72,683 ​ Coal royalties ​ ​ — ​ ​ — ​ ​ — ​ ​ 29,692 ​ ​ (29,692) ​ ​ — ​ Transportation revenues ​ ​ 40,340 ​ ​ 24,417 ​ ​ — ​ ​ — ​ ​ — ​ ​ 64,757 ​ Other revenues ​ ​ 3,559 ​ ​ 691 ​ ​ 793 ​ ​ — ​ ​ 20,650 ​ ​ 25,693 ​ Total revenues ​ $ 588,193 ​ $ 400,981 ​ $ 73,476 ​ $ 29,692 ​ $ (9,042) ​ $ 1,083,300 ​ * Recast as discussed in Note 1 – Organization and Presentation.
Schedule of current coal supply contracts allocated to performance obligations that are unsatisfied or partially unsatisfied	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2026 and ​ ​ ​ 2023 2024 2025 Thereafter Total ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Illinois Basin Coal Operations coal revenues ​ $ 762,478 ​ $ 925,042 ​ $ 344,601 ​ $ 243,600 ​ $ 2,275,721 Appalachia Coal Operations coal revenues ​ ​ 452,387 ​ ​ 574,481 ​ ​ 325,425 ​ ​ 1,600 ​ ​ 1,353,893 Total coal revenues (1) ​ $ 1,214,865 ​ $ 1,499,523 ​ $ 670,026 ​ $ 245,200 ​ $ 3,629,614 (1) Coal revenues generally consists of consolidated revenues excluding our Oil & Gas Royalties segment as well as intercompany revenues from our Coal Royalties segment .

EARNINGS PER LIMITED PARTNER _2

EARNINGS PER LIMITED PARTNER UNIT (Tables)	6 Months Ended
	Jun. 30, 2023
EARNINGS PER LIMITED PARTNER UNIT
Reconciliation of net income (loss) and EPU calculations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2023 2022 2023 2022 (1) ​ ​ (in thousands, except per unit data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP ​ $ 169,790 ​ $ 163,528 ​ $ 360,975 ​ $ 201,611 ​ Adjustment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ General partner's interest in net income attributable to ARLP ​ — ​ (2,050) ​ (1,384) ​ (3,481) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Limited partners' interest in net income attributable to ARLP ​ 169,790 ​ 161,478 ​ 359,591 ​ 198,130 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Distributions to participating securities ​ (2,396) ​ (1,720) ​ (4,828) ​ (3,272) ​ Undistributed earnings attributable to participating securities ​ (2,071) ​ (3,645) ​ (4,981) ​ (3,245) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to ARLP available to limited partners ​ $ 165,323 ​ $ 156,113 ​ $ 349,782 ​ $ 191,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average limited partner units outstanding – basic and diluted ​ 127,183 ​ 127,195 ​ 127,236 ​ 127,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per limited partner unit - basic and diluted (2) ​ $ 1.30 ​ $ 1.23 ​ $ 2.75 ​ $ 1.51 ​ (1) Recast as discussed in Note 1 – Organization and Presentation. (2) 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. The combined total of LTIP, SERP and Directors' Deferred Compensation Plan units of 2,577 and 2,896 for the three and six months ended June 30, 2023, respectively, and 3,529 and 3,289 for the three and six months ended June 30, 2022, respectively, were considered anti-dilutive under the treasury stock method .

WORKERS' COMPENSATION AND PNE_2

WORKERS' COMPENSATION AND PNEUMOCONIOSIS BENEFITS (Tables)	6 Months Ended
	Jun. 30, 2023
Black lung benefits:
Reconciliation of changes in workers' compensation liability	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ ​ (in thousands) ​ Beginning balance ​ $ 50,017 ​ $ 53,206 ​ $ 49,452 ​ $ 53,448 ​ Changes in accruals ​ 2,196 ​ 2,271 ​ 6,070 ​ 4,546 ​ Payments ​ (2,646) ​ (3,278) ​ (6,505) ​ (6,082) ​ Interest accretion ​ 551 ​ 287 ​ 1,101 ​ 574 ​ Valuation loss (gain) (1) ​ 990 ​ (5,265) ​ 990 ​ (5,265) ​ Ending balance ​ $ 51,108 ​ $ 47,221 ​ $ 51,108 ​ $ 47,221 ​ (1) Our estimate of the liability for the present value of current workers′ compensation benefits is based on our actuarial calculations. Our actuarial calculations are based on a blend of actuarial projection methods and numerous assumptions including claims development patterns, mortality, medical costs and interest rates. The valuation loss in 2023 is due to adverse claims development. The valuation gain in 2022 is due to an increase in the discount rate from 2.41% on December 31, 2021 to 4.22% on June 30, 2022.
Pneumoconiosis benefits
Black lung benefits:
Components of net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Service cost ​ $ 675 ​ $ 954 ​ $ 1,344 ​ $ 1,901 Interest cost (1) ​ 1,238 ​ 749 ​ 2,476 ​ 1,496 ​ Net amortization (1) ​ 346 ​ 259 ​ 691 ​ 519 ​ Net periodic benefit cost ​ $ 2,259 ​ $ 1,962 ​ $ 4,511 ​ $ 3,916 ​ (1) Interest cost and net amortization are included in the Other income (expense) line item within our condensed consolidated statements of income.

COMMON UNIT-BASED COMPENSATIO_2

COMMON UNIT-BASED COMPENSATION PLANS (Tables)	6 Months Ended
	Jun. 30, 2023
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, 2023 ​ 3,697,133 ​ $ 7.40 ​ ​ 75,126 ​ Granted (1) 447,225 ​ ​ 21.54 ​ ​ ​ ​ Vested (2) (1,291,330) ​ 5.02 ​ ​ ​ ​ Forfeited (145,584) ​ 6.86 ​ ​ ​ ​ Non-vested grants at June 30, 2023 2,707,444 ​ 10.90 ​ ​ 50,061 ​ (1) The restricted units granted during 2023 have certain minimum-value guarantees per unit, regardless of whether or not the awards vest. (2) During the six months ended June 30, 2023, we issued 860,060 unrestricted common units to the LTIP participants. The remaining vested units were settled in cash to satisfy tax withholding obligations of the LTIP participants.
SERP and Deferred Compensation Plans
COMMON UNIT-BASED COMPENSATION PLANS
Summary of activity in share-based plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of units Weighted average grant date fair value per unit Intrinsic value ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Phantom units outstanding as of January 1, 2023 ​ 742,540 ​ $ 20.28 ​ $ 15,088 ​ Granted ​ 49,480 ​ ​ 19.72 ​ ​ ​ ​ Settled (1) (49,331) ​ ​ 20.27 ​ ​ ​ ​ Phantom units outstanding as of June 30, 2023 742,689 ​ 20.38 ​ ​ 13,732 ​ (1) During the six months ended June 30, 2023, we purchased 27,576 ARLP common units on the open market to settle the account of a participant under the SERP. Units purchased and delivered to the participant were net of units settled in cash to satisfy tax withholding obligations.

COMPONENTS OF PENSION PLAN NE_2

COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS (Tables)	6 Months Ended
	Jun. 30, 2023
Defined benefit pension plan
Employee Benefit Plans
Components of net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Interest cost ​ $ 1,296 ​ $ 936 ​ $ 2,591 ​ $ 1,868 ​ Expected return on plan assets ​ (1,517) ​ (1,664) ​ (3,115) ​ (3,329) ​ Amortization of prior service cost ​ ​ 46 ​ ​ 46 ​ ​ 93 ​ ​ 93 ​ Amortization of net loss ​ 171 ​ 489 ​ 344 ​ 972 ​ Net periodic benefit credit (1) ​ $ (4) ​ $ (193) ​ $ (87) ​ $ (396) ​ (1) Net periodic benefit credit for the Pension Plan is included in the Other income (expense) line item within our condensed consolidated statements of income.

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	6 Months Ended
	Jun. 30, 2023
SEGMENT INFORMATION
Schedule of reportable segment results	Reportable segment results are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Coal Operations ​ Royalties ​ Other, ​ ​ ​ ​ ​ Illinois ​ ​ ​ ​ ​ Corporate and ​ ​ ​ ​ Basin Appalachia Oil & Gas Coal ​ Elimination Consolidated ​ ​ (in thousands) Three Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 355,392 ​ $ 238,242 ​ $ 33,412 ​ $ — ​ $ 14,790 ​ $ 641,836 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 16,567 ​ ​ (16,567) ​ ​ — ​ Total revenues (2) ​ ​ 355,392 ​ ​ 238,242 ​ ​ 33,412 ​ ​ 16,567 ​ ​ (1,777) ​ ​ 641,836 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (3) ​ 214,666 ​ 119,319 ​ 3,562 ​ 5,597 ​ (4,710) ​ 338,434 ​ Segment Adjusted EBITDA (4) ​ 119,551 ​ 109,573 ​ 29,050 ​ 10,970 ​ 222 ​ 269,366 ​ Capital expenditures (5) ​ 57,469 ​ 31,309 ​ 40 ​ — ​ 725 ​ 89,543 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside (1) ​ $ 313,497 ​ $ 255,682 ​ $ 39,956 ​ $ — ​ $ 10,743 ​ $ 619,878 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 14,525 ​ ​ (14,525) ​ ​ — ​ Total revenues (2) ​ ​ 313,497 ​ ​ 255,682 ​ ​ 39,956 ​ ​ 14,525 ​ ​ (3,782) ​ ​ 619,878 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (1) (3) ​ 194,697 ​ 117,369 ​ 3,582 ​ 5,398 ​ (4,624) ​ 316,422 ​ Segment Adjusted EBITDA (1) (4) ​ 97,352 ​ 124,377 ​ 37,638 ​ 9,127 ​ 839 ​ 269,333 ​ Capital expenditures ​ 35,343 ​ 22,491 ​ — ​ — ​ 4,995 ​ 62,829 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside ​ $ 715,798 ​ $ 489,501 ​ $ 68,949 ​ $ — ​ $ 30,510 ​ $ 1,304,758 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 32,080 ​ ​ (32,080) ​ ​ — ​ Total revenues (2) ​ ​ 715,798 ​ ​ 489,501 ​ ​ 68,949 ​ ​ 32,080 ​ ​ (1,570) ​ ​ 1,304,758 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (3) ​ 421,735 ​ ​ 245,118 ​ ​ 7,986 ​ ​ 10,985 ​ ​ (8,094) ​ 677,730 ​ Segment Adjusted EBITDA (4) ​ 251,559 ​ ​ 226,123 ​ ​ 59,095 ​ ​ 21,095 ​ ​ 3,441 ​ 561,313 ​ Total assets ​ 830,821 ​ ​ 470,929 ​ ​ 758,816 ​ ​ 322,926 ​ ​ 404,451 ​ 2,787,943 ​ Capital expenditures (5) ​ 119,451 ​ ​ 63,814 ​ ​ 42 ​ ​ 400 ​ ​ 1,310 ​ 185,017 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues - Outside (1) ​ $ 588,193 ​ $ 400,981 ​ $ 73,476 ​ $ — ​ $ 20,650 ​ $ 1,083,300 ​ Revenues - Intercompany ​ ​ — ​ ​ — ​ ​ — ​ ​ 29,692 ​ ​ (29,692) ​ ​ — ​ Total revenues (2) ​ ​ 588,193 ​ ​ 400,981 ​ ​ 73,476 ​ ​ 29,692 ​ ​ (9,042) ​ ​ 1,083,300 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment Adjusted EBITDA Expense (1) (3) ​ 372,286 ​ ​ 201,084 ​ ​ 6,859 ​ ​ 10,217 ​ ​ (12,568) ​ 577,878 ​ Segment Adjusted EBITDA (1) (4) ​ 175,567 ​ ​ 175,480 ​ ​ 68,473 ​ ​ 19,475 ​ ​ 3,525 ​ 442,520 ​ Total assets (1) ​ 748,291 ​ ​ 457,724 ​ ​ 734,760 ​ ​ 288,509 ​ ​ 171,389 ​ 2,400,673 ​ Capital expenditures ​ 71,890 ​ ​ 40,836 ​ ​ — ​ ​ — ​ ​ 9,256 ​ 121,982 ​ (1) Recast for the JC Resources Acquisition as discussed in Note 1 – Organization and Presentation. (2) Revenues included in the Other, Corporate and Elimination column are attributable to intercompany eliminations, which are primarily intercompany coal royalty eliminations, outside revenues at the Matrix Group and other outside miscellaneous sales and revenue activities. ​ (3) Segment Adjusted EBITDA Expense includes operating expenses, coal purchases, if applicable, and other income. Transportation expenses are excluded as transportation revenues are recognized in an amount equal to transportation expenses when title passes to the customer. ​ ​ The following is a reconciliation of consolidated Segment Adjusted EBITDA Expense to Operating expenses (excluding depreciation, depletion and amortization) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Operating expenses (excluding depreciation, depletion and amortization) ​ $ 334,402 ​ $ 316,850 ​ $ 673,125 ​ $ 578,873 ​ Outside coal purchases ​ 4,209 ​ 151 ​ 4,209 ​ 151 ​ Other expense (income) ​ (177) ​ (579) ​ 396 ​ (1,146) ​ Segment Adjusted EBITDA Expense ​ $ 338,434 ​ $ 316,422 ​ $ 677,730 ​ $ 577,878 ​ ​ (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. Management therefore is able 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. Consolidated Segment Adjusted EBITDA is reconciled to net income as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Net income ​ $ 171,305 ​ $ 163,851 ​ $ 363,983 ​ $ 202,224 ​ Noncontrolling interest ​ ​ (1,515) ​ ​ (323) ​ ​ (3,008) ​ ​ (613) ​ Net income attributable to ARLP ​ $ 169,790 ​ $ 163,528 ​ $ 360,975 ​ $ 201,611 ​ General and administrative ​ 20,130 ​ 22,480 ​ 41,215 ​ 41,102 ​ Depreciation, depletion and amortization ​ 68,639 ​ 67,690 ​ 134,189 ​ 131,830 ​ Interest expense, net ​ 6,808 ​ 9,304 ​ 16,694 ​ 18,931 ​ Income tax expense ​ 3,999 ​ 6,331 ​ 8,240 ​ 49,046 ​ Consolidated Segment Adjusted EBITDA ​ $ 269,366 ​ $ 269,333 ​ $ 561,313 ​ $ 442,520 ​ ​ (5) Capital expenditures for the three and six months ended June 30, 2023 exclude $1.1 million and $3.9 million, respectively, paid towards the Acquisition Agreement. Capital expenditures for the six months ended June 30, 2023 also exclude the $72.3 million paid for the JC Resources Acquisition (See Note 2 – Acquisitions) .
Reconciliation of consolidated Segment Adjusted EBITDA Expense to operating expenses (excluding depreciation, depletion and amortization)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Operating expenses (excluding depreciation, depletion and amortization) ​ $ 334,402 ​ $ 316,850 ​ $ 673,125 ​ $ 578,873 ​ Outside coal purchases ​ 4,209 ​ 151 ​ 4,209 ​ 151 ​ Other expense (income) ​ (177) ​ (579) ​ 396 ​ (1,146) ​ Segment Adjusted EBITDA Expense ​ $ 338,434 ​ $ 316,422 ​ $ 677,730 ​ $ 577,878 ​
Reconciliation of consolidated Segment Adjusted EBITDA to net income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ ​ 2023 2022 2023 2022 ​ ​ (in thousands) ​ Net income ​ $ 171,305 ​ $ 163,851 ​ $ 363,983 ​ $ 202,224 ​ Noncontrolling interest ​ ​ (1,515) ​ ​ (323) ​ ​ (3,008) ​ ​ (613) ​ Net income attributable to ARLP ​ $ 169,790 ​ $ 163,528 ​ $ 360,975 ​ $ 201,611 ​ General and administrative ​ 20,130 ​ 22,480 ​ 41,215 ​ 41,102 ​ Depreciation, depletion and amortization ​ 68,639 ​ 67,690 ​ 134,189 ​ 131,830 ​ Interest expense, net ​ 6,808 ​ 9,304 ​ 16,694 ​ 18,931 ​ Income tax expense ​ 3,999 ​ 6,331 ​ 8,240 ​ 49,046 ​ Consolidated Segment Adjusted EBITDA ​ $ 269,366 ​ $ 269,333 ​ $ 561,313 ​ $ 442,520 ​

ORGANIZATION AND PRESENTATION_2

ORGANIZATION AND PRESENTATION (Details) $ in Thousands		3 Months Ended			6 Months Ended
	Feb. 22, 2023 USD ($) a	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)
Ownership interests
JC Resources acquisition			$ (72,250)
Revenues		$ 641,836		$ 619,878	$ 1,304,758	$ 1,083,300
Income from operations		183,929		177,322	391,255	266,587
JC Resources
Ownership interests
Royalty acres, net | a	2,682
JC Resources acquisition	$ 72,300				72,300
Revenues		$ 2,400		3,400	$ 5,400	5,900
Income from operations				$ 2,100		$ 3,500

ACQUISITIONS (Details)

ACQUISITIONS (Details) $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 22, 2023 USD ($) a	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jan. 27, 2023 USD ($)
Asset acquisition
JC Resources acquisition				$ 64,999
Oil & gas royalty acquisition				3,935
Revenues		$ 641,836	$ 619,878	1,304,758	$ 1,083,300
Acquisition Agreement
Asset acquisition
Funding commitment						$ 35,000
Oil & gas royalty acquisition		1,100		3,900
Mineral interests in proved properties		1,900		1,900
Mineral interests in unproved properties		2,100		2,100
JC Resources
Asset acquisition
JC Resources acquisition	$ 65,000
Royalty acres, net | a	2,682
Mineral interests in proved properties	$ 25,400
Mineral interests in unproved properties	$ 37,800
Revenues		$ 2,400	$ 3,400	$ 5,400	$ 5,900

INVENTORIES (Details)

INVENTORIES (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
INVENTORIES
Coal	$ 66,383	$ 23,553
Supplies (net of reserve for obsolescence)	62,557	53,773
Total inventories, net	128,940	77,326
Reserve for obsolescence	$ 7,456	$ 6,601

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - Estimated fair value - Significant Observable Inputs (Level 2) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
FAIR VALUE MEASUREMENTS
Long-term debt	$ 429,757	$ 424,420
Total	$ 429,757	$ 424,420

LONG-TERM DEBT - Components (De

LONG-TERM DEBT - Components (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Principal
Aggregate maturities of long-term debt	$ 428,969	$ 427,009
Less current maturities	(38,194)	(24,970)
Total long-term debt	390,775	402,039
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(11,771)	(4,836)
Less current maturities	423
Total unamortized debt issuance costs	(11,348)	(4,836)
Revolving credit facility
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(8,806)	(2,702)
Term loan
Principal
Aggregate maturities of long-term debt	70,312
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(1,538)
Senior notes due 2025
Principal
Aggregate maturities of long-term debt	339,214	400,000
Unamortized Discount and Debt Issuance Costs
Unamortized debt issuance costs including current and non-current	(1,427)	(2,134)
November 2019 equipment financing
Principal
Aggregate maturities of long-term debt	15,425	21,072
June 2020 equipment financing
Principal
Aggregate maturities of long-term debt	$ 4,018	$ 5,937

LONG-TERM DEBT - Credit Facilit

LONG-TERM DEBT - Credit Facility (Details) $ in Thousands		6 Months Ended
	Jan. 13, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 09, 2020 USD ($)
Long-Term Debt
Debt issuance costs incurred		$ 11,744
Credit Agreement
Long-Term Debt
Maximum borrowing capacity	$ 425,000
Minimum liquidity to extend maturity	$ 200,000
Debt issuance costs incurred		11,700
Letters of credit outstanding		41,000
Debt available for borrowing		$ 384,000
Annual commitment fee percentage, undrawn portion		0.50%
ARLP debt arrangements requirements, debt to cash flow ratio		0.49
Interest coverage ratio	3
Actual cash flow to interest expense ratio for trailing twelve months		145.52
ARLP debt arrangements requirements, period over which the ratios are required to be maintained		12 months
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		0.10
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		0.49
Letters of credit subfacility
Long-Term Debt
Maximum borrowing capacity	$ 425,000		$ 125,000
Swingline subfacility
Long-Term Debt
Maximum borrowing capacity	15,000		15,000
Term loan
Long-Term Debt
Maximum borrowing term loan	$ 75,000
Interest rate (as a percent)	6.25%
Revolving credit facility
Long-Term Debt
Maximum borrowing capacity			$ 459,500

LONG-TERM DEBT - 2025 Senior No

LONG-TERM DEBT - 2025 Senior Notes (Details) - USD ($) $ in Thousands		1 Months Ended	6 Months Ended
	Apr. 24, 2017	Jul. 31, 2023	Jun. 30, 2023
Issuance of Senior Notes
Senior debt repaid			$ 65,474
Senior notes due 2025
Issuance of Senior Notes
Principal amount	$ 400,000
Term	8 years
Interest rate (as a percent)	7.50%
Senior debt repaid		$ 50,000	$ 60,800

LONG-TERM DEBT - Securitization

LONG-TERM DEBT - Securitization Facility (Details) - Securitization facility $ in Millions	Jun. 30, 2023 USD ($)
Long-Term Debt
Maximum borrowing capacity	$ 60
Letters of credit outstanding	11.7
Debt available for borrowing	48.3
Facility outstanding amount	$ 0

LONG-TERM DEBT - Equipment fina

LONG-TERM DEBT - Equipment financing and other (Details) $ in Millions	Jun. 05, 2020 USD ($)	Nov. 06, 2019 USD ($) payment
November 2019 Equipment Financing
Long-Term Debt
Principal amount		$ 53.1
Term		4 years
Effective interest rate (as a percent)		4.75%
Number of monthly payments | payment		47
Periodic Payment		$ 1
Balloon payment on maturity		$ 11.6
June 2020 equipment financing
Long-Term Debt
Principal amount	$ 14.7
Term	48 months
Effective interest rate (as a percent)	6.10%

INCOME TAXES - Components (Deta

INCOME TAXES - Components (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Current:
Federal	$ 3,935	$ 6,175	$ 8,247	$ 11,209
State	272	445	573	831
Total current income tax expense	4,207	6,620	8,820	12,040
Deferred:
Federal	(190)	(255)	(521)	34,665
State	(18)	(34)	(59)	2,341
Total deferred income tax expense	(208)	(289)	(580)	37,006
Income tax expense	$ 3,999	$ 6,331	$ 8,240	$ 49,046

INCOME TAXES - Tax election (De

INCOME TAXES - Tax election (Details) $ in Millions	Jun. 30, 2022 USD ($)
Change in tax accounting
Taxes
Deferred tax liability	$ 37.3

VARIABLE INTEREST ENTITIES - Ca

VARIABLE INTEREST ENTITIES - Cavalier (Details)	6 Months Ended
	Jun. 30, 2023
Cavalier Minerals | Bluegrass Minerals
Variable Interest Entities
Incentive distribution of available cash (as a percent)	25%
Cavalier Minerals
Variable Interest Entities
Ownership interest in VIE (as a percent)	96%
Cavalier Minerals | Bluegrass Minerals
Variable Interest Entities
Noncontrolling ownership interest (as a percent)	4%

VARIABLE INTEREST ENTITIES - Al

VARIABLE INTEREST ENTITIES - AllDale III (Detail) - All Dale Minerals III - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Feb. 28, 2017
Investments
Other Commitment		$ 30
Distribution after hurdles (as a percent)	25%
Specified internal rate of return (as a percent)	10%
Percentage of available cash distributed	125%
All Dale Minerals III
Investments
Ownership percentage by limited partners	13.90%

VARIABLE INTEREST ENTITIES - In

VARIABLE INTEREST ENTITIES - Investments (Detail) - USD ($) $ in Thousands				3 Months Ended		6 Months Ended
	Apr. 01, 2023	Jun. 02, 2022	Apr. 05, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investments
Contributions to equity method investments						$ 1,334	$ 20,110
Francis Renewable Energy
Investments
Contributions to equity method investments			$ 20,000		$ 20,000		20,000
Francis Renewable Energy | Francis Renewable Energy
Investments
Ownership percentage by limited partners	17.80%
NGP ETP
Investments
Funding commitment		$ 25,000
Contributions to equity method investments				$ 794	$ 110	1,334	$ 110
Contributions to investee to date				$ 5,400		$ 5,400
NGP ETP | NGP ETP
Investments
Ownership percentage by limited partners		3.60%

INVESTMENTS - Equity method (De

INVESTMENTS - Equity method (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Apr. 05, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investments
Beginning balance				$ 49,371
Contributions				1,334	$ 20,110
Equity method investment income (loss)		$ (1,994)	$ 1,585	(1,942)	2,468
Ending balance		46,789		46,789
All Dale Minerals III
Investments
Beginning balance		24,695	26,194	25,284	26,325
Equity method investment income (loss)		716	1,585	1,141	2,468
Distributions received		(960)	(1,501)	(1,974)	(2,515)
Ending balance		24,451	26,278	24,451	26,278
Francis Renewable Energy
Investments
Beginning balance		20,000		20,000
Contributions	$ 20,000		20,000		20,000
Equity method investment income (loss)		(2,620)		(2,620)
Ending balance		17,380	20,000	17,380	20,000
NGP ETP
Investments
Beginning balance		4,254		4,087
Contributions		794	110	1,334	110
Equity method investment income (loss)		(90)		(463)
Ending balance		$ 4,958	$ 110	$ 4,958	$ 110

INVESTMENTS - Non-equity method

INVESTMENTS - Non-equity method (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Investments
Equity investment without readily determinable fair value	$ 42,000	$ 42,000
Infinitum Electric
Investments
Equity investment without readily determinable fair value	$ 42,000

PARTNERS' CAPITAL - Distributio

PARTNERS' CAPITAL - Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands								6 Months Ended		12 Months Ended
	Aug. 14, 2023	May 15, 2023	Feb. 14, 2023	Nov. 14, 2022	Aug. 12, 2022	May 13, 2022	Feb. 14, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
PARTNERS' CAPITAL
Quarterly distribution paid (in dollars per unit)	$ 0.7000	$ 0.7000	$ 0.7000	$ 0.5000	$ 0.4000	$ 0.3500	$ 0.2500	$ 2.1000		$ 1.5000
Total Cash Distribution		$ 90,930	$ 91,938	$ 65,449	$ 52,338	$ 45,810	$ 32,750	$ 182,868	$ 78,560	$ 196,347

PARTNERS' CAPITAL - Narrative (

PARTNERS' CAPITAL - Narrative (Details) - Limited Partners' Capital - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended
	Jan. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Partners' capital
Increase in authorization amount	$ 93.5
Remaining authorized amount			$ 6.5
Repurchase and retire authorization	$ 100
Treasury units retired		$ 19.4
Number of units retired		929,842
Repurchase price (in dollars per unit)		$ 20.90
Aggregate
Partners' capital
Treasury units retired		$ 112.9
Number of units retired		6,390,446
Repurchase price (in dollars per unit)		$ 17.67

PARTNERS' CAPITAL - Change (Det

PARTNERS' CAPITAL - Change (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Increase (decrease) in Partners' Capital
Balance at beginning of period	$ 1,707,161	$ 1,708,026	$ 1,301,309	$ 1,294,144	$ 1,708,026	$ 1,294,144
Balance at beginning of period (in units)		127,195,219			127,195,219
Comprehensive income (loss):
Net income	171,305	$ 192,678	163,851	38,373	$ 363,983	202,224
Actuarially determined long-term liability adjustments	563	565	794	790	1,128	1,584
COMPREHENSIVE INCOME	171,868	193,243	164,645	39,163	365,111	203,808
Settlement of deferred compensation plans	(1,014)	(9,320)
Purchase of units under unit repurchase program	(1,223)	(18,209)
Common unit-based compensation	3,121	2,830	2,340	2,640
Distributions on deferred common unit-based compensation	(1,895)	(2,901)	(1,292)	(950)
Distributions from consolidated company to noncontrolling interest	(2,226)	(2,288)	(325)	(298)
Distributions to Partners	(89,035)	(89,037)	(44,518)	(31,800)
JC Resources acquisition		(72,250)
Cash retained by JC Resources in acquisition		(2,933)	(2,484)	(1,590)
Balance at end of period	$ 1,786,757	1,707,161	1,419,675	1,301,309	$ 1,786,757	1,419,675
Balance at end of period (in units)	127,125,437				127,125,437
Accumulated Other Comprehensive Income (Loss)
Increase (decrease) in Partners' Capital
Balance at beginning of period	$ (40,489)	(41,054)	(63,439)	(64,229)	$ (41,054)	(64,229)
Comprehensive income (loss):
Actuarially determined long-term liability adjustments	563	565	794	790
Balance at end of period	(39,926)	(40,489)	(62,645)	(63,439)	(39,926)	(62,645)
Noncontrolling Interest
Increase (decrease) in Partners' Capital
Balance at beginning of period	25,712	26,507	11,107	11,115	26,507	11,115
Comprehensive income (loss):
Net income	1,515	1,493	323	290
Distributions from consolidated company to noncontrolling interest	(2,226)	(2,288)	(325)	(298)
Balance at end of period	25,001	25,712	11,105	11,107	25,001	11,105
Limited Partners' Capital
Increase (decrease) in Partners' Capital
Balance at beginning of period	$ 1,721,938	$ 1,656,025	$ 1,285,725	$ 1,279,183	$ 1,656,025	$ 1,279,183
Balance at beginning of period (in units)	127,195,219	127,195,219	127,195,219	127,195,219	127,195,219	127,195,219
Comprehensive income (loss):
Net income	$ 169,790	$ 189,801	$ 161,478	$ 36,652
Settlement of deferred compensation plans	(1,014)	$ (9,320)
Settlement of deferred compensation plans (in units)		860,060
Purchase of units under unit repurchase program	$ (1,223)	$ (18,209)
Purchase of units under unit repurchase program (in units)	(69,782)	(860,060)
Common unit-based compensation	$ 3,121	$ 2,830	2,340	2,640
Distributions on deferred common unit-based compensation	(1,895)	(2,901)	(1,292)	(950)
Distributions to Partners	(89,035)	(89,037)	(44,518)	(31,800)
JC Resources acquisition		(7,251)
Balance at end of period	$ 1,801,682	$ 1,721,938	$ 1,403,733	$ 1,285,725	$ 1,801,682	$ 1,403,733
Balance at end of period (in units)	127,125,437	127,195,219	127,195,219	127,195,219	127,125,437	127,195,219
General Partners' Capital (Deficit)
Increase (decrease) in Partners' Capital
Balance at beginning of period		$ 66,548	$ 67,916	$ 68,075	$ 66,548	$ 68,075
Comprehensive income (loss):
Net income		1,384	2,050	1,431
JC Resources acquisition		(64,999)
Cash retained by JC Resources in acquisition		$ (2,933)	(2,484)	(1,590)
Balance at end of period			$ 67,482	$ 67,916		$ 67,482

REVENUE FROM CONTRACTS WITH C_3

REVENUE FROM CONTRACTS WITH CUSTOMERS - Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of revenues
Revenues	$ 641,836	$ 619,878	$ 1,304,758	$ 1,083,300
Coal sales
Disaggregation of revenues
Revenues	560,331	531,807	1,139,115	920,167
Oil & gas royalties
Disaggregation of revenues
Revenues	33,087	39,287	67,584	72,683
Transportation
Disaggregation of revenues
Revenues	30,527	35,385	60,765	64,757
Other revenues
Disaggregation of revenues
Revenues	17,891	13,399	37,294	25,693
Operating segments | Illinois Basin Coal
Disaggregation of revenues
Revenues	355,392	313,497	715,798	588,193
Operating segments | Illinois Basin Coal | Coal sales
Disaggregation of revenues
Revenues	331,813	290,389	668,723	544,294
Operating segments | Illinois Basin Coal | Transportation
Disaggregation of revenues
Revenues	21,178	21,449	42,506	40,340
Operating segments | Illinois Basin Coal | Other revenues
Disaggregation of revenues
Revenues	2,401	1,659	4,569	3,559
Operating segments | Appalachia Coal
Disaggregation of revenues
Revenues	238,242	255,682	489,501	400,981
Operating segments | Appalachia Coal | Coal sales
Disaggregation of revenues
Revenues	228,518	241,418	470,392	375,873
Operating segments | Appalachia Coal | Transportation
Disaggregation of revenues
Revenues	9,349	13,936	18,259	24,417
Operating segments | Appalachia Coal | Other revenues
Disaggregation of revenues
Revenues	375	328	850	691
Operating segments | Oil & Gas Royalties
Disaggregation of revenues
Revenues	33,412	39,956	68,949	73,476
Operating segments | Oil & Gas Royalties | Oil & gas royalties
Disaggregation of revenues
Revenues	33,087	39,287	67,584	72,683
Operating segments | Oil & Gas Royalties | Other revenues
Disaggregation of revenues
Revenues	325	669	1,365	793
Operating segments | Coal Royalties
Disaggregation of revenues
Revenues	16,567	14,525	32,080	29,692
Operating segments | Coal Royalties | Coal royalties
Disaggregation of revenues
Revenues	16,567	14,525	32,080	29,692
Other, Corporate and Elimination
Disaggregation of revenues
Revenues	(1,777)	(3,782)	(1,570)	(9,042)
Other, Corporate and Elimination | Coal royalties
Disaggregation of revenues
Revenues	(16,567)	(14,525)	(32,080)	(29,692)
Other, Corporate and Elimination | Other revenues
Disaggregation of revenues
Revenues	14,790	10,743	30,510	20,650
Elimination
Disaggregation of revenues
Revenues	(16,567)	(14,525)	(32,080)	(29,692)
Elimination | Coal Royalties
Disaggregation of revenues
Revenues	$ 16,567	$ 14,525	$ 32,080	$ 29,692

REVENUE FROM CONTRACTS WITH C_4

REVENUE FROM CONTRACTS WITH CUSTOMERS - Supply contracts (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Performance obligations unsatisfied or partially unsatisfied
Total	$ 3,629,614
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-07-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 1,214,865
Expected timing of satisfaction period	6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 1,499,523
Expected timing of satisfaction period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 670,026
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	$ 245,200
Expected timing of satisfaction period	1 year
Illinois Basin Coal
Performance obligations unsatisfied or partially unsatisfied
Total	$ 2,275,721
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-07-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 762,478
Expected timing of satisfaction period	6 months
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 925,042
Expected timing of satisfaction period	1 year
Illinois Basin Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 344,601
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	$ 243,600
Expected timing of satisfaction period	1 year
Appalachia Coal
Performance obligations unsatisfied or partially unsatisfied
Total	$ 1,353,893
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-07-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 452,387
Expected timing of satisfaction period	6 months
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 574,481
Expected timing of satisfaction period	1 year
Appalachia Coal | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Performance obligations unsatisfied or partially unsatisfied
Total	$ 325,425
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	$ 1,600
Expected timing of satisfaction period	1 year

EARNINGS PER LIMITED PARTNER _3

EARNINGS PER LIMITED PARTNER UNIT - Reconciliation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
EARNINGS PER LIMITED PARTNER UNIT
NET INCOME ATTRIBUTABLE TO ARLP	$ 169,790	$ 163,528	$ 360,975	$ 201,611
General partner's interest in net income attributable to ARLP		(2,050)	(1,384)	(3,481)
Limited partners' interest in net income attributable to ARLP	169,790	161,478	359,591	198,130
Distributions to participating securities	(2,396)	(1,720)	(4,828)	(3,272)
Undistributed earnings attributable to participating securities	(2,071)	(3,645)	(4,981)	(3,245)
Net income (loss) attributable to ARLP available to limited partners	$ 165,323	$ 156,113	$ 349,782	$ 191,613
Weighted-average limited partner units outstanding - basic (in units)	127,183,439	127,195,219	127,236,097	127,195,219
Weighted-average limited partner units outstanding - diluted (in units)	127,183,000	127,195,000	127,236,000	127,195,000
Earnings per limited partner unit - basic (in dollars per unit)	$ 1.30	$ 1.23	$ 2.75	$ 1.51
Earnings per limited partner unit - diluted (in dollars per unit)	$ 1.30	$ 1.23	$ 2.75	$ 1.51
Anti-dilutive under the treasury stock method (in units)	2,577,000	3,529,000	2,896,000	3,289,000

WORKERS' COMPENSATION AND PNE_3

WORKERS' COMPENSATION AND PNEUMOCONIOSIS - Workers' Comp (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2021
Reconciliation of changes in the workers' compensation liability
Beginning balance	$ 50,017	$ 53,206	$ 49,452	$ 53,448
Changes in accruals	2,196	2,271	6,070	4,546
Payments	(2,646)	(3,278)	(6,505)	(6,082)
Interest accretion	551	287	1,101	574
Valuation loss (gain)	990	(5,265)	990	(5,265)
Ending balance	51,108	$ 47,221	51,108	$ 47,221	$ 53,448
Estimated present value of future obligations and other information
Workers' compensation discount rate				4.22%	2.41%
Other long-term assets
Estimated present value of future obligations and other information
Receivables for traumatic injury claims	$ 4,100		$ 4,100

WORKERS' COMPENSATION AND PNE_4

WORKERS' COMPENSATION AND PNEUMOCONIOSIS - Periodic Benefit Cost (Details) - Pneumoconiosis benefits - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Black lung benefits:
Service cost	$ 675	$ 954	$ 1,344	$ 1,901
Interest cost	$ 1,238	$ 749	$ 2,476	$ 1,496
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)	Other Nonoperating Income (Expense)
Net amortization	$ 346	$ 259	$ 691	$ 519
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)	Other Nonoperating Income (Expense)
Net periodic benefit cost	$ 2,259	$ 1,962	$ 4,511	$ 3,916

COMMON UNIT-BASED COMPENSATIO_3

COMMON UNIT-BASED COMPENSATION PLANS - LTIP Grants (Details) - ARLP LTIP - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Number of units
Balance at the beginning of the period (in units)	3,697,133
Granted (in units)	447,225
Vested (in units)	(1,291,330)
Forfeited (in units)	(145,584)
Balance at the end of the period (in units)	2,707,444
Weighted average grant date fair value per unit
Balance at the beginning of the period (in dollars per unit)	$ 7.40
Granted (in dollars per unit)	21.54
Vested (in dollars per unit)	5.02
Forfeited (in dollars per unit)	6.86
Balance at the end of the period (in dollars per unit)	$ 10.90
Intrinsic value (in dollars)
Intrinsic value of outstanding grants (in dollars)	$ 50,061	$ 75,126
Other information
Common units issued	860,060

COMMON UNIT-BASED COMPENSATIO_4

COMMON UNIT-BASED COMPENSATION PLANS - LTIP Other (Details) - ARLP LTIP - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Other information
Unit-based compensation expense	$ 2.7	$ 2.1	$ 4.9	$ 4.4
Total unit-based obligation recorded	14.1		14.1
Unrecognized compensation expense (in dollars)	$ 15.4		$ 15.4
Weighted-average period for recognition of expense			1 year 1 month 6 days

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	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Number of units
Balance at the beginning of the period (in units)			742,540
Granted (in units)			49,480
Settled (in units)			(49,331)
Balance at the end of the period (in units)	742,689		742,689
Weighted average grant date fair value per unit
Balance at the beginning of the period (in dollars per unit)			$ 20.28
Granted (in dollars per unit)			19.72
Settled (in dollars per unit)			20.27
Balance at the end of the period (in dollars per unit)	$ 20.38		$ 20.38
Intrinsic value (in dollars)
Intrinsic value of outstanding grants (in dollars)	$ 13,732		$ 13,732		$ 15,088
Other information
Purchased for awards (in shares)			27,576
Unit-based compensation expense	600	$ 300	$ 1,200	$ 600
Total unit-based obligation recorded	$ 15,100		$ 15,100

COMPONENTS OF PENSION PLAN NE_3

COMPONENTS OF PENSION PLAN NET PERIODIC BENEFIT COSTS (Details) - Defined benefit pension plan - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Components of net periodic benefit cost:
Interest cost	$ 1,296	$ 936	$ 2,591	$ 1,868
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)	Other Nonoperating Income (Expense)
Expected return on plan assets	$ (1,517)	$ (1,664)	$ (3,115)	$ (3,329)
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)	Other Nonoperating Income (Expense)
Amortization of prior service cost	$ 46	$ 46	$ 93	$ 93
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)	Other Nonoperating Income (Expense)
Amortization of net loss	$ 171	$ 489	$ 344	$ 972
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)	Other Nonoperating Income (Expense)
Net periodic benefit cost	$ (4)	$ (193)	$ (87)	$ (396)

SEGMENT INFORMATION - General (

SEGMENT INFORMATION - General (Details)	6 Months Ended
	Jun. 30, 2023 segment
SEGMENT INFORMATION
Number of reportable segments	4
Number Of Coal Reportable Segments	2
Number Of Mining Complex	7

SEGMENT INFORMATION - Segment R

SEGMENT INFORMATION - Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Reportable segment results
Revenues	$ 641,836	$ 619,878	$ 1,304,758	$ 1,083,300
Segment Adjusted EBITDA Expense	338,434	316,422	677,730	577,878
Segment Adjusted EBITDA	269,366	269,333	561,313	442,520
Total assets	2,787,943	2,400,673	2,787,943	2,400,673	$ 2,728,021
Capital expenditures	89,543	62,829	185,017	121,982
Operating segments | Illinois Basin Coal
Reportable segment results
Revenues	355,392	313,497	715,798	588,193
Segment Adjusted EBITDA Expense	214,666	194,697	421,735	372,286
Segment Adjusted EBITDA	119,551	97,352	251,559	175,567
Total assets	830,821	748,291	830,821	748,291
Capital expenditures	57,469	35,343	119,451	71,890
Operating segments | Appalachia Coal
Reportable segment results
Revenues	238,242	255,682	489,501	400,981
Segment Adjusted EBITDA Expense	119,319	117,369	245,118	201,084
Segment Adjusted EBITDA	109,573	124,377	226,123	175,480
Total assets	470,929	457,724	470,929	457,724
Capital expenditures	31,309	22,491	63,814	40,836
Operating segments | Oil & Gas Royalties
Reportable segment results
Revenues	33,412	39,956	68,949	73,476
Segment Adjusted EBITDA Expense	3,562	3,582	7,986	6,859
Segment Adjusted EBITDA	29,050	37,638	59,095	68,473
Total assets	758,816	734,760	758,816	734,760
Capital expenditures	40		42
Operating segments | Coal Royalties
Reportable segment results
Revenues	16,567	14,525	32,080	29,692
Segment Adjusted EBITDA Expense	5,597	5,398	10,985	10,217
Segment Adjusted EBITDA	10,970	9,127	21,095	19,475
Total assets	322,926	288,509	322,926	288,509
Capital expenditures			400
Other, Corporate and Elimination
Reportable segment results
Revenues	(1,777)	(3,782)	(1,570)	(9,042)
Segment Adjusted EBITDA Expense	(4,710)	(4,624)	(8,094)	(12,568)
Segment Adjusted EBITDA	222	839	3,441	3,525
Total assets	404,451	171,389	404,451	171,389
Capital expenditures	725	4,995	1,310	9,256
Elimination
Reportable segment results
Revenues	(16,567)	(14,525)	(32,080)	(29,692)
Elimination | Coal Royalties
Reportable segment results
Revenues	$ 16,567	$ 14,525	$ 32,080	$ 29,692

SEGMENT INFORMATION - EBITDA Ex

SEGMENT INFORMATION - EBITDA Expense Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reconciliation of consolidated Segment Adjusted EBITDA Expense
Outside coal purchases	$ 4,209	$ 151	$ 4,209	$ 151
Other expense (income)	(177)	(579)	396	(1,146)
Segment Adjusted EBITDA Expense	338,434	316,422	677,730	577,878
Product
Reconciliation of consolidated Segment Adjusted EBITDA Expense
Operating expenses (excluding depreciation, depletion and amortization)	$ 334,402	$ 316,850	$ 673,125	$ 578,873

SEGMENT INFORMATION - EBITDA Re

SEGMENT INFORMATION - EBITDA Reconciliation (Details) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
	Feb. 22, 2023	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Reconciliation of consolidated Segment Adjusted EBITDA to net income
Net income		$ 171,305	$ 192,678	$ 163,851	$ 38,373	$ 363,983	$ 202,224
Noncontrolling interest		(1,515)		(323)		(3,008)	(613)
NET INCOME ATTRIBUTABLE TO ARLP		169,790		163,528		360,975	201,611
General and administrative		20,130		22,480		41,215	41,102
Depreciation, depletion and amortization		68,639		67,690		134,189	131,830
Interest expense, net		6,808		9,304		16,694	18,931
Income tax expense		3,999		6,331		8,240	49,046
Consolidated Segment Adjusted EBITDA		269,366		$ 269,333		561,313	$ 442,520
JC Resources acquisition			$ (72,250)
Oil & gas royalty acquisition						3,935
Acquisition Agreement
Reconciliation of consolidated Segment Adjusted EBITDA to net income
Oil & gas royalty acquisition		$ 1,100				3,900
JC Resources
Reconciliation of consolidated Segment Adjusted EBITDA to net income
JC Resources acquisition	$ 72,300					$ 72,300

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 169,790	$ 163,528	$ 360,975	$ 201,611

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		During the three months ended June 30, 2023, no director or officer adopted or terminated (i) any contract, instructions or written plan for the purchase or sale of securities of the Partnership intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) and/or (ii) any written arrangement for the purchase or sale of securities of the Partnership that meets the definition of a non-Rule 10b5-1 trading arrangement as defined in Item 408(c).
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